v0.16.1: changelog and README

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -34,7 +34,11 @@ jobs:
         run: go vet ./...
 
       - name: Test with the race detector
-        run: go test -race ./...
+        # Under the job's limit, so a package that hangs panics with the
+        # test it was in and where every goroutine waited, rather than the
+        # job ending at its deadline with nothing said: from 2026-10-15 every
+        # run did, printing nothing after internal/release.
+        run: go test -race -timeout 12m ./...
 
       - name: Build
         run: go build ./...

.gitignore

@@ -9,3 +9,5 @@ coverage.out
 /terraform-provider-llmgw/terraform-provider-llmgw
 /terraform-provider-llmgw/examples/.terraform*
 /terraform-provider-llmgw/examples/terraform.tfstate*
+# What a development server run from the checkout writes beside it.
+/secrets/

BACKLOG.md

@@ -15,6 +15,63 @@ Conventions this codebase keeps, which every item here must keep too:
 - `go test ./...`, `go vet ./...` and `govulncheck ./...` pass. No release is
   cut and nothing is deployed to the PoC cluster without being told to.
 
+## Open, in order (2026-10-20)
+
+What is left, most needed first. The detail is in the item each names.
+
+**Now: what goes wrong where it is installed.**
+1. ~~**J8**~~: done 2026-10-20. `ctl guard judge check`, and init times the judge. Left of **J3**: its load test
+   against judges on the control plane, which was stopped half way. Judges on a 4-core node of their own refused
+   0/60 at 2 at once, 13/60 at 4 and 42/60 at 10.
+2. ~~**I2 P2**~~: done 2026-10-20: the guardrails both ways, a rate per caller and server, a breaker. A portal page
+   for the servers is left, with P3 (stdio, per-person OAuth).
+3. **K**: fixes from the fabric test the operator runs with docs/large-models.md.
+
+**Soon: the customer's experience, and HA.**
+4. ~~**C24**~~: done 2026-10-21. The store's, catalog's and mirror's errors, percent signs, footer times and stale
+   forms are in the page's language. Left: the /docs documents, and a language kept per person (cookie only today).
+5. ~~**J4**~~: done 2026-10-29. The done-criterion held on the PoC: with mirror 146 stopped, `ctl model serve` of a
+   new model was fetched by the second mirror (VM 167, 10.0.0.152), placed and answered; a node without a file
+   146's address names was given 152's; what was added meanwhile reached 146 when it came back; a removal was
+   carried both ways. Found and fixed there: add-peer on a mirror machine of its own, files without checksums never
+   copied, and `mirror remove` neither recorded nor seen by the running mirror.
+6. **F5**: large imports. Done 2026-10-29: the gateway embeds what `llmgw-kb` sends as text; the slots and
+   halfvec were done before. Left: a larger store machine before a million chunks (the operator's), and the
+   embedding model on a GPU for a real import.
+
+**From Kong** (section L): L1–L5 and L9 done (v0.15.0); left of L4 is routing by cost between outside
+providers, of L5 cache-write and audio prices. L6 and L7 are llmgw-80's; L8 (A2A) when asked.
+
+**Models we can trust** (section M, 2026-10-25): M1 done (pickles refused; the explorer lists only what this
+cluster's hardware holds, with CPU and GPU tok/s). Next M2 (every download pinned and checked against Hugging
+Face, done 2026-10-30), then M5 (engines without the internet), M3, M4, M6.
+
+**Governance.**
+7. **C1**: a tenant-admin role, and forms hidden from viewers.
+8. **Audit before and after**: what a change changed, and changes made with the CLI recorded too.
+
+**When there is room.**
+9. ~~**I1**~~: done 2026-10-25 (in memory, not pgvector); left: the 40-rewordings run on the PoC.
+10. **H1**: tried on the PoC.
+11. **C4**: Parquet, and a scheduled push for usage export.
+
+**When needed.**
+12. **H5**: licences in video and audio. 13. **H3**: replicas shared, the catalog side. 14. **J7**: nginx in front
+of several control planes. 15. **J6**: rate limits per process (a note).
+
+**Done since 2026-10-16:**
+- J1, J5, I3, I4, J2.
+- Active Directory and Entra ID, tried against a Samba DC, with the console's Sign-in screen.
+- J3's code.
+- K's code and docs/large-models.md.
+- I2 P1 and the cluster's own read-only MCP server (llmgw:admin).
+- The node console's Overview; a node's page showing its version and the models on each GPU.
+
+**Not code, the operator's to decide or do:**
+- Where Alertmanager sends (its receiver is "none"): with a judge down, nobody hears.
+- The fabric test for K.
+- The PoC runs a dev build of main (v0.15.0-7-ga583359) on its control planes and nodes, the mirror v0.15.0.
+
 ---
 
 ## A. Security — do first
@@ -1073,13 +1130,19 @@ four texts per pass, while llmgw-kb sends 32 a request from 6 workers. The
 usage rows show 4.6 s a request on average, 1.8 s of it in the gateway's
 queue and 0.04 s in the guard. The GPU sat at 18–50% and the store machine
 at a third of its CPUs.
-- An embedding model's profile with many slots by default (`--parallel`
+- Done for `ctl model serve` (32 slots of 1024 tokens; `ctl model context
+  MODEL 1024 --slots 32` resizes one served before): an embedding model's profile with many slots by default (`--parallel`
   32–64, `--ctx-size` to match, `--batch-size`/`--ubatch-size` at least the
   longest chunk), or `ctl model serve` choosing that for a model with
   `capabilities.embeddings`. With the default 512, one 516-token chunk failed.
-- Embedding on the gateway's side of a document PUT, so the client sends
-  text only: today an embeddings answer is ~21 KB of JSON a chunk, and
-  the text and vector go up again (~11 KB).
+- Done (2026-10-29): embedding on the gateway's side of a document PUT.
+  `llmgw-kb` sends text only to a gateway that says `server_embeds`; the
+  gateway embeds through its own `/v1/embeddings` as the caller, 32 a batch,
+  four batches at once, waiting out a busy engine. On 40 DTIC files the
+  upload went from 25.7 to 3.5 MiB, and the ~21 KB a chunk that came down
+  is gone; on 6 files both ways gave the same 32 chunks and the same search
+  answer. Speed is the engine's either way: the PoC's bge-m3 on node02's two
+  CPU cores embeds ~0.2 chunks/s, so a real import still wants it on a GPU.
 - The store next: HNSW inserts took half of one of pg01's two cores; at a
   million chunks the vectors alone outgrow its 4 GB. halfvec (pgvector ≥
   0.7) and a larger store machine.
@@ -1429,6 +1492,14 @@ console show and add them.
 - Done 2026-10-15: llmgw's `/mcp` with picture, 3D, VLM and workflow tools,
   so a client needs no server of its own (asked by the game team); the
   shared ComfyUI replica (H3's placement side).
+- Done 2026-10-16 (v0.14.6, v0.14.7): setup lists every part with what it
+  is and its settings; three machines each run the control plane, with a
+  floating address (VRRP id from the address); a lost store primary costs no
+  request (3 s connect per member, keepalive and TCP_USER_TIMEOUT, Patroni
+  ttl 20, a standby leaves the lease alone a round after the store returns);
+  a new leader waits for its judge within the budget; a judge is asked again
+  on another machine at half its budget; init sizes the judge (2 GB, no
+  prompt cache, two cores, one judge on up to four cores on one machine).
 
 ## I. What other gateways do that llmgw does not (written 2026-10-16)
 
@@ -1442,7 +1513,13 @@ Azure/Anthropic/Bedrock/Vertex adapters, request hooks a customer plugs in,
 routing by what a request holds. Not taken: a realtime (WebSocket audio)
 API, prompt management, an `npx` install.
 
-### I1. Answers to similar questions, not only the same one (M)
+### I1. Answers to similar questions, not only the same one (M) — done 2026-10-25
+`keys cache --similar`, `router.cache.embedding_model`, `internal/router/similar.go`. Changed
+from the plan: the vectors are in the gateway's memory beside the exact answers, not a pgvector
+table. The exact cache keeps answer text out of the store on purpose (data.md), and a table of
+answers would undo that; it also works on SQLite. The usage row marks a similar hit as a hit
+(no column of its own). Open: the 40-rewordings and eval-suite runs on the PoC.
+The original item follows.
 The answer cache (`internal/router/cache.go`, C17) answers a request whose
 body is the same byte for byte. A help desk asked "how do I reset my
 password" in forty wordings asks the model forty times.
@@ -1466,6 +1543,14 @@ password" in forty wordings asks the model forty times.
   point of the run with it off.
 
 ### I2. MCP gateway: the customer's tool servers behind llmgw (L)
+P1 done 2026-10-20: HTTP servers registered (`ctl mcp`, `/api/v1/mcp/servers`,
+store `mcp_servers`), tools as `server.tool` in `/mcp`, `allowed_tools`
+grants in the tree (deny by default), credentials in the store or by
+reference, the caller named in `X-Llmgw-*` headers, time and size bounds,
+progress passed on, audit (Source `mcp`) and metrics. Left: P2, the
+guardrails both ways, a per-tool rate limit, a breaker, and a portal page;
+P3, stdio servers and per-person OAuth. The "done when" with Claude Code
+against a real server is still to try.
 `/mcp` serves llmgw's own tools. An agent inside a company also wants Jira,
 the file server, a database — each an MCP server, each today configured
 in every client with its own credentials and nobody seeing what was called.
@@ -1485,7 +1570,16 @@ in every client with its own credentials and nobody seeing what was called.
   through it, a key without the grant does not see the server's tools, and
   every call is in `ctl audit`.
 
-### I3. What llmgw adds to a request, measured (S)
+### I3. What llmgw adds to a request, measured (S) — done 2026-10-16
+`llmgw ctl bench overhead` (`internal/cli/bench_overhead.go`): an instant
+engine and the gateway in one process, four modes (direct, bare, auth, auth
+and guard patterns) at rising rates. On an Apple M5 the gateway added
+0.05–0.42 ms at p50 and at most 0.49 ms at p99, in the README.
+`TestTheGatewaysOverheadIsMeasured` runs a second of it in CI with no bound
+asserted. Left: the CPU figure is rough with everything in one process; a
+gateway in a process of its own would measure it properly. The original
+item follows.
+
 Bifrost's headline is "11 µs at 5k RPS" (its own figure, and its own pages
 disagree with it). llmgw has none, so any question about its overhead is
 answered with a guess.
@@ -1500,7 +1594,13 @@ answered with a guess.
 - Done when: the README states the overhead, with how it was measured, and
   CI runs the short version so a change that doubles it is seen.
 
-### I4. Several keys for one outside provider (S)
+### I4. Several keys for one outside provider (S) — done 2026-10-17
+`external.api_key_files` (`catalog.ExternalKey`: file, weight), one endpoint
+each in `control.externalEndpoints`, 401 retried on another key and
+`external_key_refused` notified (`router.keyRefused`). With one key a 401 is
+still the client's. `TestAKeyAtItsLimitOrRefusedIsPassedOverForAnother`. The
+original item follows.
+
 An external model has one `api_key_file` (`internal/control/control.go`,
 where external endpoints are made). A provider's limit is per key; one key
 answering 429 makes the whole fallback answer 429.
@@ -1513,9 +1613,307 @@ answering 429 makes the whole fallback answer 429.
 - Done when: with two keys and one returning 429, every request is answered
   by the other, and the console shows the one breaker open.
 
+## J. Found testing HA and single-machine installs (written 2026-10-16)
+
+Three VMs installed as HA from the setup screens, a fourth as a judge node,
+a fifth as a single 4-core, 8 GB machine; machines powered off under load.
+
+### J1. A restart refused for room another restart was giving back (S) — done 2026-10-16
+Not a wait for ever, as first written: on the 4-core VM the judge's restart
+was *refused* ("fits on no node even with this replica stopped") because the
+starter, restarted at the same time to reserve fewer cores, still held its
+old ones. Once refused, nothing tried again, so the judges kept their old
+figures. Two fixes in `internal/control/reconciler`:
+- a restart whose replacement fits once other restarts under way have gone
+  (queued, retiring or draining) waits for them, up to DrainGrace, instead
+  of being refused (`fitsAfterRestarts`, restart.go);
+- a drained replica counts a retiring one that still answers as serving, so
+  one restart after another no longer leaves the first's drained replica,
+  and the room it holds, waiting out its grace (reconciler.go).
+`TestARestartWaitsForRoomAnotherRestartWillGiveBack` is the 4-core case.
+
+### J2. A judge the leader adds is sized as init's is (S)
+When a policy names a judge the catalog lacks, the leader serves it itself
+(`internal/cli/judgekeeper.go` via `knownJudge.serveRequest` in
+`judges_known.go`, through modelserve). That judge reserves 3 GB (the
+weights, an 8192-token KV cache and a fixed gigabyte), no cores, and runs
+with llama.cpp's prompt cache, which grew one to 3.2 GB. init's judge
+(`guardModel` in `internal/cli/serverinit_cluster.go`) reserves 2 GB and
+its cores and runs with `--cache-ram 0`.
+- `modelserve` gives a guard model `--cache-ram 0`, and the keeper's
+  request the same memory and cores rule as `cpuPlan`.
+- Done when: a judge removed from the catalog comes back with the same
+  figures init would have given it.
+
+### J3. HA setup puts the judges on nodes of their own (S)
+Under load on a 4-core control plane that was also a node, 38 of 60
+requests were refused for want of a judgment. With the judges on a node of
+their own (4 cores, 32 GB, two cores each) the same test refused 2.
+- The HA setup offers a judge node or two: machines given like the store's,
+  added as nodes with a label (`llmgw.role: judge`), and the judge's
+  profile selects that label.
+- Done when: the setup installs the judges on the machines given for them,
+  and the load test above refuses no more than it did by hand.
+
+### J4. The model mirror on more than one machine (M) — done 2026-10-29, tried on the PoC
+In an HA install the mirror stays on the first machine. While it is down,
+models the nodes already have keep serving and new ones wait for it.
+- A second mirror kept in step (each machine of the store, or one more), the
+  control planes and nodes given both, the first that answers used.
+- Done when: with the first machine powered off, a model added then is
+  fetched and served.
+
+### J5. An upgrade corrects an earlier install's judge (S) — done 2026-10-16
+Built in the judge keeper (`internal/cli/judgekeeper.go`, `refit`), on the
+leader: a judge whose entry is exactly what init before v0.14.7 wrote is
+given 2 GB, `--cache-ram 0` and cores by init's rule (`refitCores`: up to
+four for one judge, two each for more), through `modelsvc.SetProfiles`,
+and its ready replicas are restarted (after J1). Its replica count is left
+as it is. One that differs is left alone and said once in the log. The
+original item follows.
+
+v0.14.6 and earlier installed two judges reserving no cores or one, with
+2 or 4 GB and the prompt cache on. On fewer than eight cores every judgment
+missed its 5 s budget and every request was refused. v0.14.7's notes say
+how to fix it by hand (`ctl model resources`, then `ctl restart`).
+- On upgrade, or on `server init` run again, a judge whose profile is still
+  exactly what an earlier init wrote is moved to today's figures and
+  restarted (after J1). One changed by hand is left alone and named.
+- Done when: a v0.14.6 single-machine install upgraded to it judges within
+  budget without anything typed.
+
+### J6. Rate limits per process (note)
+Rate limits are counted in each control plane's memory. A failover starts
+every key's minute afresh. Documented in install.md; worth a shared count in
+the store only if a customer's limits must hold across a failover.
+
+### J7. nginx in front of several control planes (S)
+`deploy/proxy/Caddyfile` sends to whichever control plane answers `/leader`.
+nginx's open-source build has no active health checks, so its `upstream`
+block would send to standbys and to a lost leader alike.
+- nginx.conf: the floating address as its one upstream, and why; or the
+  `max_fails` passive approach with what it costs.
+
+### J8. A judge budget that fits the machine (S)
+A judgment takes 2.3 s on four cores and 4.2 on two, against the 5 s
+default: two cores are close to it, and a busy machine passes it.
+- At install, after the judge is up, time three judgments. If the slowest is
+  more than half the budget, say so in the plan's closing text with the
+  choices (more cores, a GPU judge, a longer `latency_budget`, `fail:
+  open`). The budget itself is not changed without being asked.
+- Done when: an install on a machine too slow for its judge says so before
+  its first refused request.
+
+## L. Taken from Kong's AI Gateway (written 2026-10-25)
+
+From a look at Kong AI Gateway 3.9–3.16 and 2.x. Kong's open source stops at
+3.9, and only six of its AI plugins are open (proxy, prompt template,
+decorator, regex prompt guard, request and response transformer); the rest
+is Enterprise or Konnect. So nothing of Kong is embedded: the two meet over
+plain OpenAI/Anthropic HTTP, and these are the ideas worth taking. Not taken:
+prompt compression (Kong ships it as a private LLMLingua sidecar, its benefit
+unshown), prompt templates and decorators (no one has asked), Konnect's
+entity model. MCP items are llmgw-80's (I2); they are listed for it.
+
+### L1. Traces in the OpenTelemetry GenAI conventions (S) — done 2026-10-25
+`gen_ai.*` on the `inference` and `upstream` spans (`internal/router/trace.go`):
+operation, request and response model, max_tokens, temperature, top_p, the
+session as conversation id, input/output/cached tokens, the engine as
+provider. Never prompt or answer text (`TestTracesSpeakTheGenAIConventionsAndHoldNoText`).
+Prometheus already counted tokens by direction, cached apart. Left: the MCP
+calls' spans as `gen_ai.tool.*`, once /mcp is traced at all.
+
+### L2. Redacted personal data put back in the answer (S) — done 2026-10-25
+`restore: true` (`guard.Rules.Restore`), `Verdict.Restore`, `internal/router/restore.go`
+ahead of the output filter. The original item follows.
+The guardrails rewrite personal data as `[KIND_n]` (`internal/guard/gate.go`,
+`placeholders`), the same value always the same placeholder. A model that
+answers "Dear [PERSON_1]" leaves it so. Kong's sanitizer restores.
+- Per policy, `restore: true`: the placeholders of one request kept in memory
+  for its life, and swapped back in the answer, streamed too (a placeholder
+  split across two chunks held until it is whole).
+- Only into the answer to the request that held them; never stored, never in
+  usage rows or traces.
+- Done when: "write to Ayşe Yılmaz at ayse@example.com" through an enforce
+  policy reaches the model as placeholders and the client reads the real name
+  and address back.
+
+### L3. A guardrail that is someone else's service (S) — done 2026-10-25
+`guard.Service` (`internal/guard/service.go`), policy `services`, asked
+before the judge on input and once on the whole answer. The original item follows.
+Customers may be required to use one: Azure Content Safety, Lakera, NeMo
+Guardrails, an in-house classifier. Kong's AI Custom Guardrail is a
+templated HTTP call with an expression for "block".
+- A detector kind `http`: URL, headers from secret files, a body template
+  with the text, a JSON path that says blocked and one that says why;
+  timeout and `fail` as the judge's. Checked on input, output or both.
+- Done when: a policy with an `http` detector against a test service blocks
+  what it says to, and a service that does not answer is treated as `fail`
+  says.
+
+### L4. Routing by latency and by cost, and failover by priority (M) — latency done 2026-10-25
+`endpoint.Registry.ObserveTTFT`, `scheduler.Latency()` in `chat`. Failover in tiers is
+what `fallbacks` already does (local, then an outside model when no room). Left:
+routing by cost between several outside providers. The original item follows.
+The scorers (`internal/router/scheduler/scorers.go`) know sessions, queues
+and KV cache. Kong also balances by measured latency, by tokens or cost
+used, and in priority tiers.
+- A `latency` scorer: a moving average of time to first token per endpoint.
+- Fallbacks in tiers: local replicas first, then an outside provider, with
+  the tier said in the usage row.
+- Done when: with two replicas of one model, one on a slower card, `latency`
+  sends most of the traffic to the faster and the slower still gets some.
+
+### L5. Prices by kind and by cache (S–M) — done 2026-10-25
+`cached_per_1k`, charged on the answer's `cached_tokens`. A budget in money was already
+there (`keys limits --budget`). Not done: cache-write and audio/video token prices —
+no engine llmgw runs reports them, and no provider it reaches is billed by them yet.
+The original item follows.
+`catalog` prices are per million input/output tokens and per picture/mesh.
+Kong prices cached reads and cache writes apart, and audio, image and video
+tokens apart, and limits by cost.
+- Price fields for cached input and by modality; the usage row's cost from
+  them; a budget limit in money as well as tokens (`keys limits --cost`).
+- Done when: a request with 90% cached prompt costs what the cached rate says.
+
+### L6. REST APIs as MCP tools (M) — for llmgw-80, beside I2
+Kong turns OpenAPI operations into MCP tools. A company with an internal
+REST API and no MCP server could offer it to agents through `/mcp`:
+`llmgw ctl mcp add hr --openapi https://hr.internal/openapi.json`, each
+operation a tool, under the same grants, audit, guardrails and rate as I2.
+
+### L7. MCP sign-in by the MCP spec (M) — for llmgw-80, part of I2 P3
+Kong's MCP OAuth2: llmgw's `/mcp` as an OAuth 2.1 resource server (protected
+resource metadata, tokens checked by JWKS against the company's identity
+provider), and a token exchanged for a short-lived one per upstream server
+rather than one long-lived secret.
+
+### L8. A2A (S, when asked)
+Agent-to-agent traffic through the gateway: agent cards' URLs rewritten to
+llmgw's, calls audited and traced. The standard is young; wait for a
+customer.
+
+### L9. llmgw behind Kong, written down (S) — done 2026-10-25
+docs/kong.md, tried with kong:3.9: plain route and ai-proxy, keys passed on;
+Kong 3.9 counts no completion tokens of a stream. The original item follows.
+A customer that already runs Kong puts llmgw behind it: `ai-proxy` with
+`provider: openai` and `upstream_url` at llmgw (3.9, open source), or a plain
+route. A page in docs/ with the configuration, tried against Kong 3.9 in a
+container, and what Kong's token accounting sees.
+
+## M. Models from Hugging Face we can trust (written 2026-10-25)
+
+The user asked how we know a model fetched from Hugging Face is safe. Two
+questions: whether its files can run code on our machines, which we can
+close, and whether the model itself was trained to misbehave, which no scan
+proves — only who published it, an eval before it serves, and the
+guardrails narrow that. What existed: `--trust-remote-code` refused, no
+repository Python fetched, ComfyUI nodes pinned to a commit, engines
+hash-pinned and run as `llmgw-engine`, mirror versions pinned to a commit
+and never overwritten. What did not: everything below.
+
+### M1. Weights in a pickle format refused (S) — done 2026-10-25
+`.bin`, `.pt`, `.pth`, `.ckpt`, `.pkl` run code as they are loaded, which is
+how the malicious models found on Hugging Face work. The node refuses such a
+source, or a mirror set holding one, before fetching anything; a model being
+added or given such a source is refused; vLLM and SGLang downloading a model
+by its id are given `--load-format safetensors`. The explorer hides a repository with neither GGUF nor safetensors
+(under "runs here", ticked by default) and does not offer a repository's
+pickle files. `allow_pickle: true` on a model lets it through, on purpose. On the
+PoC, `triposr` (`hf:stabilityai/TripoSR/model.ckpt`) is the one model that
+needs it.
+
+### M2. Every download pinned and checked against Hugging Face (M) — done 2026-10-30
+Done: what is added from Hugging Face is pinned (the file's commit URL, or
+`--revision` for vLLM/SGLang) with each file's sha256 in the origin; the node
+refuses and deletes a copy that is not it, naming both, and keeps the
+checksum beside a cached file; the mirror checks what `ctl model serve`
+fetches, `mirror add` a Hugging Face URL. Left: models declared in the
+settings are not pinned, the admin page's and the console's mirror fetches
+send no sha256, and adapters by hub id are not pinned.
+- `hf:org/repo/file` follows `main` and is checked by nothing; a bare
+  `org/repo` given to vLLM is downloaded by vLLM, of whatever `main` is.
+  Both: resolve to the commit when the model is added, keep it in the
+  catalog's origin, and fetch that commit only (`--revision` for vLLM).
+- The sha256 Hugging Face publishes for each LFS file compared on every
+  path, and a file that differs removed: `mirror add`, the manager, the
+  node's `hf:` and http sources, mirror set files with no sha recorded.
+- Done when: a file changed on Hugging Face after a model was added is
+  refused by the node with both checksums named.
+
+### M3. Hugging Face's own scan (S)
+Hugging Face scans every file (pickle imports, ClamAV, partners' scanners)
+and marks a file unsafe. Ask for it with the repository listing; refuse an
+unsafe file, show the result on the mirror page and in the catalog's origin.
+The API field has to be confirmed first.
+
+### M4. Publishers we trust, and the rest asked about (S)
+An allow-list of organisations in the cluster's settings (Qwen, meta-llama,
+mistralai, google, microsoft, …). A model from anyone else is added only by
+an admin who says so, and who said it is kept in the origin. The PoC already
+serves four community models whose training nobody here checked.
+
+### M5. Engines without the internet (M)
+The firewall is inbound only, so an engine that was made to run code can
+send what it reads anywhere. With weights from the mirror the engines need
+no egress: an nft output rule for the engine user (allow the mirror, the
+cluster, loopback), systemd hardening of the agent's engines
+(`NoNewPrivileges`, `ProtectSystem`, private /tmp). Agent itself still root.
+
+### M6. An eval before a new model serves (S)
+`eval` and `canary` exist; make a new model from an untrusted publisher
+(M4) serve only after its eval suite passes, so a model trained to answer
+wrongly on a trigger has at least been asked the suite.
+
+## N. Strata, all the way up (written 2026-10-30)
+
+Strata (opt-in engine since 2026-10-29) is wired at the agent: adapter, `llmgw strata-serve`, install pinned by
+digest, metrics in vLLM's names, GPU memory of child processes. Above the agent it is invisible: a Strata model is
+served only from a definition written by hand. In order:
+
+**A. What is broken.**
+- N1. A Strata named by hand (`engines.strata.dir`) was never reported: no Probe. Done 2026-10-30.
+- N2. Its engine runs in a session of its own and survived a stop, holding the card and the RAM: the supervisor
+  now finds what left the group before signalling it. Done 2026-10-30.
+- N3. Host memory: the experts live in RAM (40 GB for Qwen3.8-Flash-Next IQ2_XS, 72–136 GB for Unsloth's) and
+  nothing reserved it. A Strata profile added now reserves what its size takes, from the table (N5), unless it says
+  `min_memory_gb`. Done 2026-10-30.
+- N4. Pascal and Volta: installed (CUDA 12.9 build) and then refused (7.0 floor). Floor now 6.0. Done 2026-10-30.
+
+**B. Offered where models are chosen.**
+- N5. A table of Strata's families and sizes (qwen, coder, swift, unsloth, gyro, nvfp4, qwen36, deepseek41) with
+  download and RAM, from Strata 0.2.7's setup (internal/strata/models.go); the catalog refuses an unknown family or
+  size, and requires `--size`. Done 2026-10-30. Speeds measured: Qwen3.8-Flash-Next IQ2_XS 70–87 tok/s on an RTX 6000.
+- N6. `modelplan`, `ctl model plan` and `ctl model serve` offer "Strata on one card + N GB RAM" for a model it runs;
+  a large MoE that fits no card is not "fits nowhere". Done 2026-10-30, without a speed (one measurement so far).
+- N7. The web serve page, the explorer's fit, the console's serve form: the same choice. Done 2026-10-30.
+- N8. `--context`/`--parallel` tied to `context_length`/`max_output`; `ctl model context` takes Strata.
+
+- N7b. The mirror page's Strata tab: every family and size, fetch (GGUF) or serve (packs Strata fetches itself:
+  NVFP4, DeepSeek V4.1). Done 2026-10-30. Community `strata-ple` packs Strata 0.2.7 does not list stay unservable;
+  running them would mean starting the engine past Strata's setup (`--pack`, `--native`, `--ple-gguf`).
+
+**C. Operating it.**
+- N9. `ctl engine-check strata`: the flags of setup.py and server.py, which drift between versions.
+- N10. `ctl engine-build NODE strata cuda12|cuda13`, as vLLM has.
+- N11a. Strata's per-replica state directories (engine-home/strata/<replica>) are left behind when a replica stops;
+  remove them with it.
+- N11. Disk for the prepared pack and draft layer (and DeepSeek V4.1's 240–280 GB), cleaned with the weights; a
+  first start's preparation within the startup timeout.
+- N12. docs/install.md: Strata in the engines table, a section with a profile, its memory and first-run time;
+  `doctor` and `server init` checking or offering it.
+
+**D. What Strata can do that llmgw does not ask of it yet.**
+- N13. Several cards of one node (`--gpus`, `--gpu-roles`): larger packs on a customer's multi-GPU machines.
+- N14. `--calibrate` once per node and model, kept.
+- N15. Vision, KV types, experts from SSD when RAM is short (`--low-ram`) in the plan and forms.
+- N16. Versions apart from llmgw's releases (Strata's signed update feed, `--rollback-engine`); offline bundles.
+- N17. `cache_salt` for KB isolation if Strata caches prefixes; `ctl bench` with its metrics path.
+
 ## D. Facts worth knowing before starting
 
-- Admin API: `127.0.0.1:9090`, no auth, `ctlClient` in `internal/cli/ctl.go`.
+- Admin API: `127.0.0.1:9090`, behind the token in
+  `/var/lib/llmgw/admin-token` (A5), `ctlClient` in `internal/cli/ctl.go`.
   Metrics on `:9091` with `/prometheus/targets` beside them.
 - Store: `internal/store`, migrations under `internal/store/migrations/{sqlite,postgres}`;
   the PoC runs PostgreSQL under Patroni.

CHANGELOG.md

@@ -18,12 +18,651 @@ is only released once its **exit criterion** is met, not when its code lands.
 | v0.11.0 | — | High availability from setup, the setup and console screens, usage sums and per-tenant alerts | released |
 | v0.12.0 | — | The cluster's settings in the store, in force when changed; the firewall switch; wipe | released |
 | v0.13.0 | — | The whole system stopped and started from one command; Qwen3Guard judges, on a GPU and CPUs together | released |
-| v0.14.0 | — | Knowledge bases: documents from people's own machines, kept apart per tenant, answered from | released (v0.14.1: adapters, the tree over the API, the firewall on every machine; v0.14.2: pictures from ComfyUI; v0.14.3: 3D models as jobs; v0.14.4: any ComfyUI workflow as a job, presets, licences; v0.14.5: picture and 3D models that add themselves; v0.14.6: setup that explains every part and lets it be chosen, the gateway on all three HA machines) |
+| v0.14.0 | — | Knowledge bases: documents from people's own machines, kept apart per tenant, answered from | released (v0.14.1: adapters, the tree over the API, the firewall on every machine; v0.14.2: pictures from ComfyUI; v0.14.3: 3D models as jobs; v0.14.4: any ComfyUI workflow as a job, presets, licences; v0.14.5: picture and 3D models that add themselves; v0.14.6: setup that explains every part and lets it be chosen, the gateway on all three HA machines; v0.14.7: the judge sized for its machine; v0.14.8: sign-in with Active Directory, several keys for one outside provider; v0.14.9: sign-in set up from the console, a node's console that shows the machine) |
+| v0.15.0 | — | The company's MCP tools and VS Code through the gateway; guardrails that ask outside services and put redacted values back; answers to similar questions | released (v0.15.1: Strata, a 125B model of experts on one card; a second mirror kept in step; pickled weights refused; a served model's context changed; v0.15.2: a served model moved to more cards; v0.15.3: a model stopped and kept, or removed with its files) |
+| v0.16.0 | — | Weights pinned to a commit and checked against what Hugging Face published; documents embedded by the gateway; Strata offered where models are chosen; cluster upgrades that say how far they are | released (v0.16.1: the mirror's Strata tab, Strata's ready-made packs) |
 | v1.0.0 | 5 | What phase 5 has left: precise KV routing proven on vLLM, the block cost picker, defragmentation across NVLink domains, prefill/decode disaggregation | planned |
 
 Until v1.0.0 the minor version is the breaking one: configuration formats and Go
 APIs change between minors without a deprecation period.
 
+## v0.16.1 — 2026-10-30
+
+The mirror page's Strata tab, Strata's ready-made packs served with Strata fetching them, and two fixes found
+serving Strata's models: repositories that keep each size in a directory, and DeepSeek on cards its engine does not
+run on.
+
+**Upgrading.**
+- No migrations. The control planes carry the tab, the plan and the serving; the agents carry the refusal of a
+  Strata profile its card cannot run (`llmgw ctl upgrade v0.16.1`). Mirrors need nothing new.
+
+### Added
+
+- **The mirror page's Strata tab.** Every family and size Strata runs, with its download, the RAM it keeps and where
+  it would run here; a GGUF size fetched into the mirror in one press (checked against Hugging Face's checksums),
+  and the packs Strata fetches itself — NVFP4, DeepSeek V4.1 — served at once, their repository the source.
+  `ctl model plan` and `ctl model serve` take those repositories too, and the explorer names a `strata-ple`
+  repository for what it is: part of a pack Strata knows, or one Strata 0.2.7 does not.
+
+### Fixed
+
+- **A repository that keeps each quantisation in a directory of its own** (ISTA-DASLab's `IQ2_XS/`, `IQ3_S/`) listed
+  no weights: its file tree is now read recursively, by the explorer, the plan and `ctl model serve`.
+- **DeepSeek V4.1 offered on a card its engine was not built for.** Strata's DeepSeek engine runs on RTX 30 (compute
+  8.6) and newer; on a Turing card the tab and the plan offered it, and Strata's setup refused it once placed. Now
+  neither offers it there, the tab says why, and the agent refuses such a profile before starting it.
+
+## v0.16.0 — 2026-10-30
+
+Weights pinned to the commit they were added at and checked, by the nodes and the mirror, against the sha256
+Hugging Face published; the documents `llmgw-kb` sends embedded by the gateway; Strata offered by the plan, `ctl
+model serve`, the explorer and the serve forms; and cluster upgrades that tell the nodes together, say how far they
+are, and do not fail a node that came back on the version.
+
+**Upgrading.**
+- No migrations. Upgrade the control planes, then the nodes (`llmgw ctl upgrade v0.16.0`), then each mirror's host
+  (`sudo llmgw upgrade v0.16.0 --service llmgw-mirror`).
+- A node checks what it fetches against the catalog's checksums only once it runs this version; until then it
+  fetches as before.
+- A model added from Hugging Face is now pinned when it is added, which needs the registry reachable from the
+  control plane; one it cannot be looked up in is refused, saying why. Models already in the catalog are left as
+  they are.
+- A Strata profile must say `--size` as well as `--family`, and both must be ones Strata runs.
+- `llmgw-kb` sends text alone to a gateway of this version; an older `llmgw-kb` keeps working, sending vectors.
+
+### Added
+
+- **Strata offered where models are chosen.** For a repository of a family Strata runs, `ctl model plan` offers "one
+  card with Strata, experts in RAM" with the RAM it takes, `ctl model serve --engine strata` (or the plan's choice)
+  builds its profile, the Hugging Face explorer lists it as running here, and the mirror's serve form serves such a
+  version on Strata. Strata's families and sizes are known: the catalog refuses one it does not run and reserves the
+  RAM a size keeps its experts in.
+- **The gateway embeds the documents `llmgw-kb` sends.** A document may be sent as its passages' text alone; the
+  gateway embeds them through its own `/v1/embeddings` as the caller, 32 at a time and four batches at once,
+  waiting out a busy engine rather than failing the document. About a kilobyte a passage leaves the machine instead
+  of a vector down and up again, some thirty times more. `llmgw-kb` does so with a gateway that says it can
+  (`server_embeds` in a collection's answer); `--embed-here` keeps the old way.
+- **Weights pinned to a commit, and checked against what Hugging Face published.** A model added from Hugging Face
+  (`hf:`, a resolve URL on a branch, or a repository vLLM or SGLang downloads) is pinned to the commit it is at
+  then — the file's URL at that commit, or `--revision` — and each file's published sha256 goes in its origin. A node
+  refuses and deletes a copy that is not it, naming both checksums; the mirror does the same for what `ctl model
+  serve` fetches, and `llmgw mirror add` for a Hugging Face URL (`--sha256` for others). Nodes need this version to
+  check; older ones fetch as before.
+
+### Fixed
+
+- **A cluster upgrade that sat silent, or stopped on a node that had upgraded.**
+  - The nodes of a wave are told together, each saying when it is done, and what is still awaited is said every 30
+    seconds; before, each was told in turn, up to five minutes each, with nothing on the screen.
+  - The control plane takes the node registering again on the version as done: the agent's answer, sent a moment
+    before it exits, could be lost, and a node that had upgraded was failed as "older than v0.10.4".
+  - The agent's download no longer ends with its connection (a control plane restarting, leadership moving), and the
+    control plane waits longer than the download may take; a second request while one runs is refused.
+  - A cordoned or draining node upgraded is done; a node whose idle model stopped meanwhile is done once nothing on it
+    is starting; a node not connected is passed over and named at the end rather than stopping every node after it.
+  - The console's node upgrade waits as long as the control plane, and offers no development version.
+  - systemd never gives up restarting the agent (`StartLimitIntervalSec=0`), in units written from now on.
+
+- **Strata.** One named by hand in `agent.yaml` was never reported, so never placed on; its engine, which leaves the
+  server's process group, is now stopped with it; Pascal and Volta, which its CUDA 12 build runs, were refused.
+- **A name with a slash in it, asked through a standby control plane.** `llmgw ctl kb delete Demo/hr` on a standby
+  was answered 405: the standby passed the request on to the leader with `Demo%2Fhr` unescaped, two segments instead
+  of one. The path now reaches the leader as it was sent.
+
+## v0.15.3 — 2026-10-29
+
+A model stopped and kept, or removed with its files; the second mirror fixed where it was tried.
+
+**Upgrading.**
+- No migrations. The control planes carry stop, start and purge; the nodes need nothing new.
+- The mirrors carry the fixes: on each mirror's machine, `sudo llmgw upgrade v0.15.3 --service llmgw-mirror`.
+  A mirror with a peer then works out the checksums its older files lack, once, which reads every such file.
+
+### Added
+
+- **A model stopped and kept, and a model removed with its files.** `llmgw ctl model stop|start MODEL`: none of its
+  replicas run, it stays in the catalog with its files, and start runs it again scaled as it was; requests are told an
+  administrator stopped it. `llmgw ctl model remove MODEL --purge` (`DELETE /api/v1/models/{name}?purge=true`) also
+  deletes every version of it on the mirror, a second mirror following, and the nodes' copies once its replicas have
+  stopped; what another model uses stays. Both are in the console's model menu.
+
+### Fixed
+
+- **`llmgw mirror add-peer` on a mirror with a machine of its own.** It set the second mirror up and then
+  failed for want of the control plane's server.yaml; now it prints the `llmgw ctl config set mirror.peers`
+  to run on a control plane.
+- **Models fetched before checksums were kept reach the second mirror.** A mirror kept in step copies only what it
+  can check, and those files had no sha256; a mirror with peers now works theirs out and records them, once.
+- **A file removed with `llmgw mirror remove` is gone from the mirror's answers too.** The running mirror kept
+  reporting a file it had fetched as present for a week after it was removed, so a control plane could place a
+  model on a file that was not there; and the removal was not recorded, so a mirror kept in step copied it back.
+
+## v0.15.2 — 2026-10-29
+
+A served model moved to more cards, or fewer, while it is served.
+
+**Upgrading.**
+- No migrations, and nothing changes until the command is used. The control
+  planes carry it; the nodes need nothing new.
+
+### Added
+
+- **A served model moved to more cards, or fewer.** `llmgw ctl model gpus
+  MODEL N [--profile P] [--in-place]`, `POST /api/v1/models/{name}/gpus`, and
+  GPUs… in the console's model menu. How many cards of one node each replica
+  uses: tensor parallel for vLLM, SGLang and TensorRT-LLM, checked against
+  the model's KV heads, and the layers split for llama.cpp. Refused for a
+  count no node has, or whose cards would not hold the model and its
+  context, with the figures; its replicas are then started again on it, one
+  by one, beside the old — or, with `--in-place` when there is no room
+  beside them, each stopped first.
+
+## v0.15.1 — 2026-10-29
+
+A 125B model on one card, a second mirror, and weights that run code
+refused. Strata runs as an engine: a mixture-of-experts model with its
+experts in RAM, served from one 24 GB card. A second model mirror keeps in
+step with the first, so an HA install has no single machine left. Pickled
+weights are refused unless a model says otherwise. A served model's context
+can be changed in place. The explorer says how fast a model would answer
+here before it is fetched, and a card in the wrong PCIe slot is said so.
+
+**Upgrading.**
+- No migrations. Upgrade the control planes before the nodes, for the
+  pickle refusal below.
+- A model whose weights are in a pickle format (`.bin`, `.pt`, `.pth`,
+  `.ckpt`, `.pkl`) stops being placed: its node refuses the source. Give it
+  its safetensors or GGUF, or add it again with `allow_pickle: true`
+  (`llmgw ctl model add -f`) if its files were checked. Look at the
+  models' sources before upgrading the nodes: one ending in
+  `.ckpt` or `.bin`, or a mirror version holding `pytorch_model.bin`. Upgrade the control planes first: a node on
+  this version refuses those weights until its control plane can say
+  `allow_pickle`.
+- Strata is opt-in: nothing installs it until `engines` or an
+  `engine_overrides` entry names a version (`0.2.7`).
+
+### Added
+
+- **Strata as an engine: a 125B model of experts on one card.** Strata
+  (github.com/Niko1221/Strata) keeps a model's experts in RAM and the ones
+  used most in VRAM. On an RTX 6000 24 GB with 251 GB of RAM it serves
+  Qwen3.8-Flash-Next 125B (IQ2_XS) at 70–87 tokens a second to one client;
+  more clients share about that, its slots buying fairness rather than
+  throughput on one card. It runs a few families only — Qwen3.8-Flash-Next
+  and its variants, Qwen3.6-35B-A3B, DeepSeek V4.1-Flash — each named in a
+  profile's args with `--family` and `--size`
+  (`--family qwen --size IQ2_XS --context 32768`). The source is the
+  directory of the model's GGUF files, or the repository, which Strata then
+  downloads itself, pinned. The agent installs it on an NVIDIA node of
+  x86-64: its source pinned by digest, in a Python environment, and its
+  release's engine checked against the digest GitHub publishes — the CUDA 13
+  build for Turing and newer on driver 580, the CUDA 12.9 build for Pascal
+  to Ada, a V100 included, on driver 575. A replica prepares its model the
+  first time (minutes; its draft layer is a 5 GB download) and loads in
+  about a minute and a half after. One card of one node per replica, for
+  now; not in an offline bundle, its packages coming from PyPI.
+
+- **A served model's context, changed.** `llmgw ctl model context MODEL
+  TOKENS [--slots N]`, `POST /api/v1/models/{name}/context`, and Context
+  length… in the console's model menu. The catalog, the engine's arguments and
+  the memory change together, checked against what the model was trained for
+  and what its cards hold; its replicas are then started again one by one. The
+  models API shows `context_length` and `max_output`.
+
+- **A second model mirror, kept in step.** In a three-machine install the setup screens put one on a database machine
+  (`--second-mirror 1|2`). An install with one mirror gets one with `sudo llmgw mirror add-peer user@host`.
+  - **In step:** each mirror reads the other every thirty seconds. It copies what it lacks, checksum checked, and
+    removes what the other removed, even if it was down at the time (`llmgw mirror serve --peer`).
+  - **Control planes:** they name both (`mirror.peers`) and use whichever answers.
+  - **Nodes:** while one mirror is down, a node is given a model's file on the other.
+
+  This takes away the last single point of an HA install: with the first machine off, models are still added and
+  fetched.
+
+### Fixed
+
+- **An engine that computes in a process of its own group was not its
+  replica's.** A GPU replica read as running on the CPU, and the memory it
+  held on its card as somebody else's, which placement then kept free of
+  other work. A process the replica started, at any remove, is now the
+  replica's. And what a replica computes on, once sent, was never sent
+  again: a wrong reading kept from before an agent's restart stayed wrong.
+  It is sent again when it changes, and read again when a GPU replica was
+  kept as the CPU.
+
+- **VS Code's sign-in lost its place through the sign-in page**, so the
+  prompt to confirm came every time; a link to the same gateway by plain
+  http could take an https setting down to http; and a new build of the
+  extension was not installed over an old one (the command now says
+  `--force`).
+- **The install guide's recordings were not checked for secrets**, only
+  the page; every frame is now.
+- **MCP server fields could not be emptied**, an address could carry a
+  password, the cluster's own server could not be changed from the
+  console, and a grant to a key that does not exist was said done.
+- **A guardrail service two policies named was asked as the first said**,
+  not the stricter; a `null` answer read as safe; and with `restore` the
+  request log kept the answer with the redacted values back in it.
+- **What an engine downloads by a Hugging Face id was not held to the
+  pickle refusal** — an adapter by its id, a TensorRT-LLM model's; a model
+  with either now needs `allow_pickle`.
+- **`server init` run again on a machine already set up was refused its
+  memory**, as on an 8 GB install fixing its certificate with `--host`, and
+  judges that would not be installed (no mirror) were counted.
+- **Removing an MCP server left its sealed credential in the store**, and
+  replacing a credential under another header kept the old one sent. A
+  server's secrets now go when it no longer reads them.
+- **A cloned repository could point the VS Code extension at another
+  gateway.** `llmgw.gatewayUrl` is a machine setting now, never taken from a
+  workspace.
+- **A node's memory bandwidth could be measured in its cache** on a busy
+  node, and was 0 after a reconnect until the next heartbeat. The buffer is
+  at least eight times the processor's last cache.
+- **A project kept in the cluster could have its questions embedded outside
+  it.** The similar-question cache now asks the embedding model as the
+  question's project would, external fallbacks refused, and skips a model
+  that is itself outside. Its comparing no longer holds the cache's lock,
+  which every project's lookups waited on.
+- **Restored values were left as placeholders in streamed tool calls**, in
+  completions and in reasoning, and a value with a quote in a whole answer's
+  tool-call arguments broke their JSON.
+- **An outside guardrail service read what `redact` had taken out**, and a
+  streamed answer was sent to it twice. The docs now say a service stops a
+  streamed answer only under `stream: buffer_all`.
+- **A replica found slow once could stay unused.** Its time to first token
+  is forgotten after five minutes without an answer, so it is tried again.
+- **Weights that run code got past the refusal in four ways.** A mirror
+  version already on a node was used without being looked at again; a
+  `?query` or `#fragment` on an `hf:` source hid the file's name; `.pt2` was
+  not on the list; and a profile could write `--load_format`,
+  `--trust_remote_code` or an abbreviation such as `--trust-remote`, which
+  vLLM and argparse read as the flag, or give SGLang `--load-format`. All
+  refused now. TripoSR's preset says `allow_pickle`, without which it could
+  not be added, and a shared ComfyUI environment takes its first member's.
+- **A temperature written as a string was refused.** Since the GenAI traces
+  read it, `"temperature": "0.7"` got a 400 before reaching the engine; it
+  is read loosely again, for the trace only.
+- **A reused answer could carry another caller's personal data.** With
+  `restore: true` and the answer cache on, two callers' requests that
+  redacted to the same text shared one answer — with the first caller's
+  address put back in it. Such requests are now never answered from the
+  cache nor kept in it.
+- **Granting a server's tools could take others away; revoking could close
+  a level to every tool.** A level with no tool list sees what the levels
+  above grant; giving it its first list made it see only that list. And a
+  level left with an empty list was closed to every tool, which the screens
+  did not show. Now a first list starts from the nearest list above, taking
+  a server away leaves the rest or goes back to no list, the screens say
+  when a level above keeps granted tools out of reach and which levels are
+  closed, and the console reads and writes the level at once rather than
+  from what it loaded.
+- **Similar questions about different pictures got each other's answer.**
+  A question with a picture, a sound or a file in it is reused only when it
+  is the same request.
+
+### Added
+
+- **A card in the wrong PCIe slot is said so.** Each agent reads how every
+  card is linked — the fastest generation card and slot allow together, and
+  the lanes in use — against the card's own most, from the kernel (the
+  driver's figure is what card and slot allow together); a card on fewer lanes or
+  an older generation is a node warning, with what it carries and what it
+  could, on the dashboard, the console and in `llmgw doctor`.
+- **And on a web page, `/admin/mcp`.** For administrators: the same list,
+  adding a server with its credential sealed, testing it and listing its
+  tools, granting them in the tree beside that level's other grants and
+  limits, revoking, changing, replacing the credential, turning it off,
+  removing; and the line that points an agent at this gateway's `/mcp`.
+  In English and Turkish; every change in the audit log, the secret not.
+- **The company's MCP servers in the console.** A screen of its own: each
+  server with its state, who has its tools, its rate, the names of the
+  credentials it is sent and its address; add one with a bearer token or
+  a header kept sealed, test it and list its tools, grant them to a team,
+  project, organization, person or key beside that level's other grants,
+  revoke, change, replace the credential, turn off, remove.
+- **And on the cards, as this cluster would lay it out.** The explorer's
+  **GPU tok/s** and a repository's files give one reply's speed for each
+  layout the planner offers here — one card, tensor parallel across a
+  node's cards, llama.cpp's layer split, a pipeline across nodes on a
+  fabric — the fastest of them, with the layout in the tooltip. From each
+  card's memory bandwidth by its model name, NVLink or PCIe between a
+  node's cards, and InfiniBand or RoCE between nodes; a cluster of mixed
+  classes is judged class by class. A model of experts reads 1.6 times its
+  active share, as Qwen3-Coder-30B-A3B did on cuda01's RTX 6000 (144
+  tok/s; qwen3-vl-8b Q8: 62).
+- **How fast a model would answer on a CPU, before it is fetched.** Each
+  agent measures how fast its node's memory reads when it starts (`Host`
+  gets `mem_bandwidth_gbs`, the node's view `mem_bandwidth_gbs`); the
+  explorer's **CPU tok/s** column and a repository's GGUF files say about
+  how many tokens a second one reply gets on the fastest node that holds
+  the model — the bandwidth over the bytes a token reads, its active part
+  for a model of experts. Calibrated on the PoC against llama.cpp's own
+  timings: within 15% from 1.5B to 14B.
+- **The explorer lists what this cluster can run.** Judged by the nodes
+  as they are now — every card's memory and compute capability, every
+  node's RAM — through the same planner as serving a model, rather than a
+  size picked from a list. A model too big for any node, in FP8 without a
+  card of 8.9, in MLX, or in neither GGUF nor safetensors, is left out and
+  counted; the page says what it judged by. With cards, safetensors repositories are
+  listed beside GGUF. On a repository's page a file too big for the
+  cluster is shown with what it needs and no Fetch button.
+- **Weights that run code are refused.** Python pickles — `.bin`, `.pt`,
+  `.pth`, `.ckpt` — run whatever they hold when loaded, which is how the
+  malicious models on Hugging Face work. The node refuses such a source,
+  or a mirror version with one in it, before fetching it; adding such a
+  model is refused; vLLM and SGLang downloading a model by its id read its
+  safetensors only; the mirror page marks the file. `allow_pickle: true`
+  on a model lets it through on purpose. The mirror's explorer no longer
+  lists a repository with nothing a node loads (no GGUF, no safetensors)
+  while "runs here" is ticked, and a repository's pickle files are not
+  offered, only counted. BACKLOG M lists what is next:
+  checksums against Hugging Face everywhere, its own scan, trusted
+  publishers, engines without the internet.
+
+## v0.15.0 — 2026-10-25
+
+The company's tools and editors through the gateway, and guardrails that
+can lean on others. Its own MCP servers sit behind llmgw's `/mcp` under the
+guardrails, a rate and a breaker. VS Code gets the gateway's models from an
+extension the gateway serves. A guardrail policy can ask an outside
+service, and can put redacted values back in the answer. Chat goes to the
+replica answering soonest. A similar question can get the answer already
+given. A cached prompt can be priced apart. Traces follow the OpenTelemetry
+GenAI conventions, and Kong is written down from trying it. Also an install
+guide with every screen, at `/install`.
+
+**Upgrading.**
+- Migrations 0049 (`mcp_servers`), 0050 (their rate and breaker) and 0051
+  (`projects.cache_similar`), applied when the control plane starts.
+- `llmgw server init` now refuses a machine that would serve models without
+  the memory for them: the starter model and the judges need 12 GB on one
+  machine, where 8 GB was said before. `--no-model`, `--no-guard-model` or
+  `--no-node` make it fit. A running cluster is not checked again.
+- Traces carry the GenAI conventions' `gen_ai.*` attributes beside the
+  `llmgw.*` ones, which stay; docs/install.md, "Tracing", lists them.
+- Nothing else changes until it is turned on: `services` and `restore` in a
+  guardrail policy, `keys cache --similar` with
+  `router.cache.embedding_model`, `cached_per_1k` in a price.
+
+### Added
+
+- **Answers to similar questions.** `llmgw keys cache --similar 0.95` also
+  gives a chat question the answer already given to one like it in the same
+  conversation, compared by `router.cache.embedding_model`, as
+  `x-llmgw-cache: similar` with the similarity. Held in memory beside the
+  exact answers; nothing written to the store but the setting.
+- **A cached prompt costs the cached rate.** `cached_per_1k` in a price
+  charges the prompt tokens an engine or provider read from its cache (the
+  answer's `cached_tokens`) at their own rate; without it they cost what any
+  prompt token does, as before.
+- **Chat goes to the replica answering soonest.** The router keeps each
+  replica's time to first token, smoothed over its last answers, and the
+  `chat` profile scores by it beside the queue and the KV cache: of two
+  replicas of one model, the one on the slower card or the busier host gets
+  less, and a replica not yet measured is tried.
+- **llmgw and Kong, written down** ([docs/kong.md](docs/kong.md)): Kong 3.9
+  in front of llmgw by a plain route or its `ai-proxy`, each team's llmgw
+  key passed on; Kong as a provider behind llmgw; and that Kong 3.9 counts
+  no completion tokens of a streamed answer, so bill from llmgw's usage.
+- **A guardrail that is someone else's service.** A policy's `services`
+  asks Azure Content Safety, Lakera, NeMo or a company's own classifier over
+  HTTP: a body template, keys from files, dotted paths to where the answer
+  says unsafe and why, on input, output or both, block or flag, and the
+  policy's `fail` when it does not answer.
+- **Redacted values put back in the answer.** `restore: true` on a guardrail
+  policy's input: the model reads `[EMAIL_1]`, the client reads its own
+  address in the reply, streamed or not. Only the request's own values, held
+  in memory for its life; the output rules read the answer as the client
+  will.
+- **Traces in the OpenTelemetry GenAI conventions.** An inference request
+  and each attempt at an engine carry `gen_ai.operation.name`, the requested
+  and the answering model, `max_tokens`, `temperature` and `top_p` when set,
+  the session as `gen_ai.conversation.id`, and the input, output and cached
+  tokens, and an attempt the engine that answered as `gen_ai.provider.name`.
+  Tools that read the conventions show llmgw's calls as model calls with no
+  dashboard of their own. No prompt or answer text is ever in a span.
+- **llmgw for VS Code.** An extension of llmgw's own, served by every gateway
+  at `/setup/vscode/llmgw.vsix` with that gateway's address in it, made from
+  the binary itself: plain JavaScript, no dependencies, no build, and so no
+  marketplace needed at a site with no internet. It offers the gateway's chat
+  models to VS Code's language-model API — the chat's model picker, agent
+  mode, and every extension that asks VS Code for a model — with the sizes
+  and the tool and vision capabilities the catalog says, streamed, with tool
+  calls and their results both ways. **VS Code** is a tool on the account
+  page's **Connect your editor**: a key, the one-line install, and an **Open
+  in VS Code** link that hands the key to the extension, which keeps it in
+  VS Code's secret storage. **llmgw: Sign In** opens that page with a state
+  of its own; a link without it is confirmed first, the gateway named.
+- **An install guide with every screen, at `/install`.** From three bare
+  Ubuntu machines to a first answer: what each machine needs and how to
+  check it, the release fetched and checked, the setup screens one by one,
+  the system's state, and a first request with a key from the account page.
+  The screens are a real three-machine install, recorded and kept as
+  terminal frames — sharp at any size and a few kilobytes — with each
+  session played back on request; the administrator's password and every
+  key were masked before it was kept. `/about` says more of what llmgw does
+  (documents, guardrails, sign-in, high availability, pictures and 3D), and
+  its install steps are the ones of today, leading to the guide.
+- **The company's MCP tools under the guardrails, a rate and a breaker.**
+  - **The answer:** the caller's policies read a tool's answer as the prompt it becomes. An instruction planted in a
+    ticket is withheld as a pasted one would be, and personal data is redacted.
+  - **The arguments:** they are read before they leave, so a secret pasted into one does not reach the company system.
+  - **Rate:** `ctl mcp add --rate N` allows each caller N calls a minute to a server.
+  - **Breaker:** five failures in a row take a server out for a minute, its tools off the list.
+
+- **How fast the judge is, measured.** `llmgw ctl guard judge check` (and `POST /api/v1/guard/judges/check`) works
+  out whether the judge keeps up with requests. It times three judgments of a 280-token prompt, then a burst at once,
+  and sets both against the policies' wait. It says ok, tight or slow, about how many requests a second can be judged,
+  and what to do: more cores, more judges, a GPU judge, a longer wait, or `fail: open`. `server init` runs it once the
+  judge is up. If the machine is too slow it says so before the next steps, not after the first refused request.
+
+- **The company's own MCP servers through llmgw's `/mcp`.** `llmgw ctl mcp add jira --url … --secret-file
+  Authorization=FILE` registers one; `/mcp` then lists its tools as `jira.search` beside llmgw's own. Only keys granted
+  them see them: `llmgw keys limits --tools 'jira.*'`, patterns at any level of the tenancy tree. None granted anywhere
+  is none. The server's credentials stay on the control planes, kept in the store sealed or read by reference. The
+  server is told the calling key, person and project. Each call is bounded in time and size, and its progress passes
+  on to a streaming client. Every call is in the audit log with its arguments' size and digest, never their text. The
+  admin API has `/api/v1/mcp/servers`.
+- **The cluster as a read-only MCP server.** Registered as `llmgw ctl mcp add llmgw --url llmgw:admin` and granted
+  as `llmgw.*`, its tools say what `llmgw ctl` does:
+  - `cluster_status`, `list_nodes`, `list_models`, `list_replicas`, `explain_placement`, `node_logs`;
+  - nothing that changes the cluster.
+
+  It is answered in the control plane's own process, so there is no token to keep and every control plane serves it.
+  The admin API serves the same at `POST /api/v1/mcp`. `ctl mcp add --bearer-file` keeps a token, sent as
+  `Authorization: Bearer`.
+
+- **Large models across cards and nodes.** For a model of experts on more than one card, the plan now adds vLLM's
+  `--enable-expert-parallel`. It reads the expert count from `config.json` under any of its names, and sizes a model
+  that also reads pictures by its `text_config`. Several nodes are offered in any number, not only powers of two. Each
+  way now says what it needs of a card, part by part (weights, context, engine), and of all its cards together. This
+  shows in `ctl model plan`, in the console's Serve a model, and in a serve job's first step. The serve form checks that
+  a longer context still fits. `ctl model serve --env KEY=VALUE` puts engine variables such as `NCCL_DEBUG=INFO` on
+  every node. docs/large-models.md has the rules, the commands, and a checklist for bringing a model up on a fabric.
+
+- **Machines of the judges' own in a three-machine install.** The setup screen asks for up to two judge machines after
+  the store's two; `server init` takes `--judge-node user@host` for each. Each is added as a node labelled
+  `llmgw.role: judge`, and the judge's profile selects it, so the judges run there alone. Under load on a 4-core
+  control plane that was also a node, 38 of 60 requests were refused for want of a judgment. With the judges on a node
+  of their own, 2 were. A node with an `llmgw.role` label takes only profiles whose node selector asks for that role,
+  so no other model is placed on the judges' machine.
+
+### Fixed
+
+- **A machine too small for the models it would serve is said so first.**
+  The control plane that is also a node, serving the starter model and two
+  judges, needs about 10.5 GB. On 8 GB the install finished every step and
+  then had no room for the starter. Now the setup's checks fail its memory
+  with what it would serve, and `server init` refuses before it installs
+  anything, naming `--no-model`, `--no-guard-model` and `--no-node`.
+
+- **Turkish pages are Turkish to the end.**
+  - **Errors:** those from the store, catalog and mirror that a page shows ("not found", "not empty", "already in the
+    catalog", the settings changed meanwhile, and others) are now in the page's language.
+  - **Percent:** a percentage is written the language's way: `%93` in Turkish, `93%` in English.
+  - **Footer:** the time at the foot of a page is in the language's date form.
+  - **Stale forms:** they are refused with a sentence in that language rather than "bad request".
+
+- **`llmgw keys limits` no longer clears the limits it was not given.** Setting one limit at a scope wrote the whole
+  row, so `--tools 'jira.*'` alone took away that scope's rate, budget and model list. Only what is given changes now.
+  `--replace` writes every limit, as the console's limits form does.
+
+- **The plan refused tensor parallelism past a model's KV heads.** Qwen3-235B, with four KV heads, had no way to run
+  on eight cards, though vLLM gives each card a copy of a head. A width that is a multiple of the KV heads is now
+  offered, as is one that divides them.
+- **A big model on a slow mirror was failed while it downloaded.** The startup timeout counted the download, so
+  hundreds of gigabytes at a few hundred MB/s ran past twenty minutes and the replica was started again from nothing.
+  The timeout now runs from when a node's download last moved.
+
+- **The judge init installs is no longer replaced by the leader's own.** Just after the control plane started, the
+  leader saw a policy naming a judge that init was still fetching, and served one itself. Its entry replaced init's, so
+  a second judge ran with the leader's sizing, and with judge machines it ran off them. The leader now waits ten minutes
+  after it starts before it serves a judge itself. If someone adds one while it fetches, theirs stays.
+- **A judge the leader serves by itself is sized as init's is.** When a guard policy names a judge the catalog lacks,
+  the leader serves it. That judge reserved 3 GB and no cores, and ran llama.cpp's prompt cache, which grew one to
+  3.2 GB. Without cores of its own, a judgment on a busy node missed its 5 s budget, and `fail: closed` refused the
+  request. It now gets what `server init` gives its judges: 2 GB, two cores each (fewer on a small node), and no
+  prompt cache. Every judge served through `modelserve` runs with `--cache-ram 0`.
+
+## v0.14.9 — 2026-10-19
+
+Sign-in set up from the console, with Active Directory tried before it is
+kept. A node's console now shows what the machine is doing, and a node's web
+page shows what it runs. Also fixes found trying Active Directory against a
+Samba domain controller on the test cluster. Sign-in through it, nested
+groups and a disabled account suspended by the sync all worked there.
+
+**Upgrading.**
+- No migration.
+- `auth.ldap` and `auth.oidc` are in the cluster's settings, as before. A
+  block written into `server.yaml` on a cluster with a store was never
+  read; the log said so. Put it in with `llmgw ctl config edit`, or set it up
+  again from the console's Sign-in screen.
+- A Samba DC's own autogenerated certificate is refused (a negative serial
+  and no SAN). Give it one from a CA.
+
+### Added
+
+- **Sign-in set up from the console.** Under People → Sign-in, `sudo llmgw` shows how people get in: single sign-on,
+  Active Directory and SCIM, each on or off. It also shows the directory's last sync. **E** sets up Entra ID from the
+  tenant and client IDs. **D** sets up Active Directory, and the directory is tried before it is kept: each server
+  reached and bound, how many people may sign in, how many are in each group. Nothing is kept if a step fails. The
+  password, client secret and SCIM token are kept in the store as `store:auth/…`, sealed by the master key. The
+  domain's CA goes into the settings (`auth.ldap.ca`), so no file has to be put on each control plane. The admin API
+  has the same: `GET /api/v1/auth`, `POST /api/v1/auth/ldap/test` and `PUT /api/v1/auth/secrets/{name}`.
+- **A node's page says what it runs.** It now shows the agent's version, marked when the control plane runs another,
+  and the engines with their versions. Each GPU row now names the models loaded on that card, and each engine row its
+  GPUs.
+- **`sudo llmgw` on a node opens on what the machine is doing.** A new Overview screen shows the agent's state and
+  version, each control plane it dials and whether it answers, every GPU with the models on it, the engines running
+  here, the free space for weights and engines, and the agent's warnings of the last hour. It is read on the node
+  itself, every three seconds, so it needs no admin token and works while the control plane is out of reach.
+
+### Fixed
+
+- **A broken `auth.ldap` no longer stops every control plane.** It is the cluster's setting. A CA file that one
+  machine could not use made `llmgw server` exit on every control plane, and no `ctl config` could then put it right.
+  Directory sign-in is now turned off on that control plane, with an error in its log. Local accounts still sign in.
+- **A second `llmgw server` on a machine stops before it competes to lead.** `llmgw server check` (no such command)
+  ran a whole server. Its ports were taken, yet it went on to hold the leader's lease for three hours while the real
+  control planes stood by. `server` now refuses words it does not know and takes its ports before anything else.
+- **The single sign-on and Active Directory guides said `server.yaml`.** On a cluster with a store, `auth` is in the
+  cluster's settings and the file's block is not read. They now say `llmgw ctl config edit`, and what certificate a
+  domain controller needs.
+
+## v0.14.8 — 2026-10-18
+
+Sign-in with an on-premises Active Directory, and Entra ID made safe for
+people in many groups. Also several keys for one outside provider, and a
+measure of what the gateway adds to a request.
+
+**Upgrading.**
+- Migration 0048 adds the `user_directory` table, applied when the control
+  plane starts.
+- Nothing changes until `auth.ldap` is set; docs/install.md, "Active
+  Directory", has an example. It has been tested against a fake directory,
+  not yet against a real domain controller.
+- A judge installed by an earlier `server init` is refitted by the leader
+  by itself (below); the steps given for v0.14.7 are no longer needed.
+
+### Added
+
+- **Sign-in with Active Directory** (`auth.ldap`). People sign in on the gateway's form with their AD username or mail
+  and password, checked against the domain controllers over LDAPS or StartTLS. Groups, nested ones included, give
+  staff roles and places in the tree, as with OIDC. Accounts are tied to the `objectGUID` and made at first sign-in
+  when `create_accounts` is on. Every 15 minutes the leader reads the directory. People disabled or deleted there are
+  suspended and reinstated when they come back; roles and memberships follow their groups. A sync that would suspend
+  more than half the accounts is refused. See docs/install.md, "Active Directory".
+
+- **Several keys for one outside provider.** An external model takes `api_key_files`, each with an optional weight, in
+  place of `api_key_file`. Each key is an endpoint of its own (`external:MODEL#1`, `#2`), so a key answering 429 is
+  passed over while its breaker is open and the request goes to another. A key answering 401 is passed over too, and
+  `external_key_refused` is sent, naming the endpoint, never the key. Usage records which key answered by that name.
+
+- **`llmgw ctl bench overhead`**: what the gateway adds to a request, measured against an engine that answers at
+  once. Gateway and engine run in one process on loopback, so no cluster is needed. The load is sent straight to the
+  engine and through the gateway: bare, with authentication and accounting, and with the guardrails' pattern checks.
+  It reports p50 and p99 latency, what the gateway added, and a rough CPU per thousand requests. On an Apple M5 the
+  gateway added 0.05–0.42 ms at p50 and at most 0.49 ms at p99 (README).
+
+### Fixed
+
+- **Entra ID's groups past 200 no longer take a role away.** For someone in more than 200 groups Entra sends none in
+  the token, only a pointer to Graph. That was read as no groups, so an administrator lost their role at the next
+  sign-in. Their role and memberships are now left as they were, and an error is logged saying what to change in the app
+  registration. docs/install.md has an Entra ID section.
+- **An account made by SCIM or OIDC could not be reinstated.** Setting it active was refused as "never approved".
+- **An upgrade refits the judge an earlier `server init` installed.** Upgrading to v0.14.7 left such a judge as it was:
+  no cores or one, 2 or 4 GB, the prompt cache on. On fewer than eight cores every request was refused until it was
+  fixed by hand. Now the leader finds a judge whose entry is exactly what an earlier init wrote and gives it 2 GB, no
+  prompt cache and cores by today's rule (up to four for one judge, two each for more). It then restarts the judge's
+  replicas onto that. The number of replicas is left as it is. A judge whose entry was changed by hand is left alone,
+  and the log says so once.
+- **A restart is no longer refused for room another restart is giving back.** With every core of a node reserved, two
+  models restarted together, one to need more and one less (as after `ctl model resources` on a judge and a starter),
+  had the first refused: "fits on no node even with this replica stopped", though the second was about to give back
+  its cores. A restart now waits for other restarts under way, up to the drain grace, before it is refused. A drained
+  replica also counts a replica being restarted that still answers as serving, so replicas restarted one after
+  another no longer wait out the five-minute grace each.
+
+## v0.14.7 — 2026-10-16
+
+The judge installed by `server init` sized for what it does. On a machine
+of fewer than eight cores v0.14.6 left every judgment past its budget, so
+`fail: closed` refused every request. A single-machine install of v0.14.7
+on a 4-core VM passed 20 of 20, and on 8 cores 20 of 20 under load.
+
+**Upgrading.**
+- No migration.
+- **Upgrading does not change a judge already in the catalog.** v0.14.6
+  and earlier installed two judges, reserving no cores or one, and 2 or
+  4 GB. To give them what they need:
+  `llmgw ctl model resources qwen3guard-0.6b --memory 2 --cores 2`, then
+  `llmgw ctl restart --model qwen3guard-0.6b`. The two then need four cores
+  on a single machine; below that, a longer `latency_budget` or
+  `fail: open`.
+- On a node whose cores are all reserved, `ctl restart --model` cannot
+  start the new replica beside the old one and waits. Stop the old engine
+  process, and the replica comes back with the new figures.
+
+### Fixed
+
+- **Both judges fit an 8 GB machine again.** v0.14.6 had `server init` reserve 4 GB a judge replica. That figure came
+  from one replica at 3.2 GB after a day of traffic. The growth was llama.cpp's prompt cache, up to 8 GB by default,
+  which a judge never reuses: each text it reads is different. On a 4-core, 8 GB machine the second judge then fitted
+  nowhere ("has 7 GB of memory with 1 free, needs 4"). The judge now runs with `--cache-ram 0`, uses about 1.6 GB and
+  stays there, and reserves 2.
+- **One machine runs one judge, on up to four cores.** A second replica on the same machine shares its cores and is
+  lost with it, so it bought nothing but half the speed of each. `server init` on a single machine now serves one judge
+  on up to four cores (2.3 s a judgment where two on two cores took 4.2). Where there will be other nodes, it serves two
+  on two cores each, as in HA setups. `--judge-replicas` and the setup's Copies still choose.
+- **A judge gets the two cores it needs.** v0.14.6 gave each judge replica one core on machines under eight. A judgment
+  of about 280 tokens takes 8.0 s on one core, 4.2 s on two and 2.3 s on four, against the 5 s budget, so on a 4-core
+  machine every judgment timed out and every request was refused. Where there are two judges, each now reserves two
+  cores (one only below four CPUs), and the one judge of a single machine up to four; the starter has what is left, or
+  shares when nothing is. A judge on two cores stays close to its budget: give it more cores or a GPU, or raise
+  `latency_budget`, where requests must not wait.
+
 ## v0.14.6 — 2026-10-16
 
 Setup that says what each part of an install is and lets every one be

README.md

@@ -40,7 +40,9 @@ Releases track the roadmap phases; see [CHANGELOG.md](CHANGELOG.md).
 | v0.11.0 | — | High availability from setup, the setup and console screens, usage sums and per-tenant alerts | released |
 | v0.12.0 | — | The cluster's settings in the store, in force when changed; the firewall switch; wipe | released |
 | v0.13.0 | — | The whole system stopped and started from one command; Qwen3Guard judges, on a GPU and CPUs together | released |
-| v0.14.0 | — | Knowledge bases: documents from people's own machines, kept apart per tenant, answered from | released (v0.14.1: adapters, the tree over the API, the firewall on every machine; v0.14.2: pictures from ComfyUI; v0.14.3: 3D models as jobs; v0.14.4: any ComfyUI workflow as a job, presets, licences; v0.14.5: picture and 3D models that add themselves; v0.14.6: setup that explains every part and lets it be chosen, the gateway on all three HA machines) |
+| v0.14.0 | — | Knowledge bases: documents from people's own machines, kept apart per tenant, answered from | released (v0.14.1: adapters, the tree over the API, the firewall on every machine; v0.14.2: pictures from ComfyUI; v0.14.3: 3D models as jobs; v0.14.4: any ComfyUI workflow as a job, presets, licences; v0.14.5: picture and 3D models that add themselves; v0.14.6: setup that explains every part and lets it be chosen, the gateway on all three HA machines; v0.14.7: the judge sized for its machine; v0.14.8: sign-in with Active Directory, several keys for one outside provider; v0.14.9: sign-in set up from the console, a node's console that shows the machine) |
+| v0.15.0 | — | The company's MCP tools and VS Code through the gateway; guardrails that ask outside services and put redacted values back; answers to similar questions | released (v0.15.1: Strata, a 125B model of experts on one card; a second mirror kept in step; pickled weights refused; a served model's context changed; v0.15.2: a served model moved to more cards; v0.15.3: a model stopped and kept, or removed with its files) |
+| v0.16.0 | — | Weights pinned to a commit and checked against what Hugging Face published; documents embedded by the gateway; Strata offered where models are chosen; cluster upgrades that say how far they are | released (v0.16.1: the mirror's Strata tab, Strata's ready-made packs) |
 | v1.0.0 | 5 | What phase 5 has left: precise KV routing proven on vLLM, the block cost picker, defragmentation across NVLink domains, prefill/decode disaggregation | planned |
 
 As of v0.6.0 a cluster runs unattended: agents report their hardware, the
@@ -183,6 +185,8 @@ Every page is also in the binary: `llmgw docs`, or **Manual** in the console.
   cluster that exists
 - [docs/kubernetes.md](docs/kubernetes.md) — the control plane on
   Kubernetes with the Helm chart, and why GPU nodes stay outside it
+- [docs/kong.md](docs/kong.md) — llmgw behind Kong Gateway, or Kong behind
+  llmgw: the configuration, what Kong counts, and which to choose
 - [docs/fabrics.md](docs/fabrics.md) — InfiniBand fabrics and NVLink: what
   llmgw needs of them, checking a node with `llmgw doctor`, and what to look at
   when a replica spanning nodes will not run
@@ -257,6 +261,33 @@ Add `--json` to any command for machine-readable output.
 says nothing about which of six constraints bit, so it prints every candidate
 considered and the reason it was rejected.
 
+## What llmgw adds to a request
+
+Measured with `llmgw ctl bench overhead`. It starts an engine that answers
+at once and a gateway in front of it, in one process on loopback. It sends
+the same load straight to the engine and through the gateway, and reports
+what the gateway added. Run on an Apple M5 (10 CPUs, load about 2) on
+2026-10-16, 10 s a step, 72,000 requests with none failed:
+
+| Through the gateway | added at p50 | added at p99 |
+|---|---|---|
+| bare | 0.06–0.24 ms | 0.10–0.33 ms |
+| with authentication and usage accounting | 0.05–0.32 ms | 0.09–0.37 ms |
+| with the guardrails' pattern checks as well | 0.10–0.42 ms | 0.15–0.49 ms |
+
+The range is across 100 to 2,000 requests a second. The overhead was
+*lowest* at 2,000, most likely because a busier processor keeps its cores
+awake. The guardrails' judge model is not in these figures: a judgment
+takes seconds on CPUs (see [install.md](docs/install.md)) and is a model's
+time, not the gateway's.
+
+The command also prints the gateway's CPU per thousand requests. Gateway,
+engine and load share one process there, so that figure is rough (0.04 to
+0.65 s per thousand in the run above); the latency is the one to quote.
+Figures from a VM on a busy host move with the host: run it where you will
+deploy, and keep the load it prints beside the result. CI runs a one-second
+version on every change (`TestTheGatewaysOverheadIsMeasured`).
+
 ## Running the router
 
 ```sh
@@ -284,8 +315,9 @@ within 1.24x of idle while 500 concurrent batch requests run, against 58x with
 admission off.
 
 Routing profiles select how endpoints are scored: `chat` favours session
-affinity, `batch` favours the shortest queue, `long-context` favours free KV
-cache. Pick one per model in the config, or per request with the
+affinity and the replica that has been answering soonest (its time to first
+token, smoothed), `batch` favours the shortest queue, `long-context` favours
+free KV cache. Pick one per model in the config, or per request with the
 `x-llmgw-profile` header.
 
 ## sim-engine

api/gen/llmgw/v1/agent.pb.go

@@ -1206,9 +1206,12 @@ type Host struct {
 	CpuFlags []string `protobuf:"bytes,5,rep,name=cpu_flags,json=cpuFlags,proto3" json:"cpu_flags,omitempty"`
 	// nvidia_driver is the driver version, empty when there is none. A card
 	// without a driver is not a GPU anything can use.
-	NvidiaDriver  string `protobuf:"bytes,6,opt,name=nvidia_driver,json=nvidiaDriver,proto3" json:"nvidia_driver,omitempty"`
-	unknownFields protoimpl.UnknownFields
-	sizeCache     protoimpl.SizeCache
+	NvidiaDriver string `protobuf:"bytes,6,opt,name=nvidia_driver,json=nvidiaDriver,proto3" json:"nvidia_driver,omitempty"`
+	// mem_bandwidth_gbs is how fast the memory reads, in GB/s, measured when
+	// the agent started: what decides a model's speed on the CPU. 0 unknown.
+	MemBandwidthGbs float64 `protobuf:"fixed64,7,opt,name=mem_bandwidth_gbs,json=memBandwidthGbs,proto3" json:"mem_bandwidth_gbs,omitempty"`
+	unknownFields   protoimpl.UnknownFields
+	sizeCache       protoimpl.SizeCache
 }
 
 func (x *Host) Reset() {
@@ -1283,6 +1286,13 @@ func (x *Host) GetNvidiaDriver() string {
 	return ""
 }
 
+func (x *Host) GetMemBandwidthGbs() float64 {
+	if x != nil {
+		return x.MemBandwidthGbs
+	}
+	return 0
+}
+
 // Storage is one filesystem a node keeps weights on.
 //
 // Per filesystem rather than per configured directory: free space belongs to
@@ -1579,7 +1589,14 @@ type GPU struct {
 	// is then 1000 + 100 × card + device, uuid the instance's (MIG-…), and
 	// memory the instance's share; utilization_percent stays zero, because no
 	// driver measures it per instance.
-	Mig           *MIGDevice `protobuf:"bytes,22,opt,name=mig,proto3" json:"mig,omitempty"`
+	Mig *MIGDevice `protobuf:"bytes,22,opt,name=mig,proto3" json:"mig,omitempty"`
+	// How the card is linked to its host: the fastest generation card and
+	// slot allow together, the card's own fastest, and the lanes in use and
+	// the card's most. Zero when the driver did not say.
+	PcieGen       int32 `protobuf:"varint,23,opt,name=pcie_gen,json=pcieGen,proto3" json:"pcie_gen,omitempty"`
+	PcieGpuGen    int32 `protobuf:"varint,24,opt,name=pcie_gpu_gen,json=pcieGpuGen,proto3" json:"pcie_gpu_gen,omitempty"`
+	PcieWidth     int32 `protobuf:"varint,25,opt,name=pcie_width,json=pcieWidth,proto3" json:"pcie_width,omitempty"`
+	PcieWidthMax  int32 `protobuf:"varint,26,opt,name=pcie_width_max,json=pcieWidthMax,proto3" json:"pcie_width_max,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -1768,6 +1785,34 @@ func (x *GPU) GetMig() *MIGDevice {
 	return nil
 }
 
+func (x *GPU) GetPcieGen() int32 {
+	if x != nil {
+		return x.PcieGen
+	}
+	return 0
+}
+
+func (x *GPU) GetPcieGpuGen() int32 {
+	if x != nil {
+		return x.PcieGpuGen
+	}
+	return 0
+}
+
+func (x *GPU) GetPcieWidth() int32 {
+	if x != nil {
+		return x.PcieWidth
+	}
+	return 0
+}
+
+func (x *GPU) GetPcieWidthMax() int32 {
+	if x != nil {
+		return x.PcieWidthMax
+	}
+	return 0
+}
+
 // MIGDevice is which card a MIG instance is carved from, and how.
 type MIGDevice struct {
 	state       protoimpl.MessageState `protogen:"open.v1"`
@@ -2943,8 +2988,12 @@ type Heartbeat struct {
 	// is not handed out. Empty from an agent that does not measure it, or from
 	// one that could not this time.
 	GpuForeignMemoryMb []int32 `protobuf:"varint,19,rep,packed,name=gpu_foreign_memory_mb,json=gpuForeignMemoryMb,proto3" json:"gpu_foreign_memory_mb,omitempty"`
-	unknownFields      protoimpl.UnknownFields
-	sizeCache          protoimpl.SizeCache
+	// mem_bandwidth_gbs is how fast the node's memory reads, in GB/s, once
+	// the agent has measured it — in the background after it starts, so a
+	// registration usually has none yet. 0 means not measured.
+	MemBandwidthGbs float64 `protobuf:"fixed64,20,opt,name=mem_bandwidth_gbs,json=memBandwidthGbs,proto3" json:"mem_bandwidth_gbs,omitempty"`
+	unknownFields   protoimpl.UnknownFields
+	sizeCache       protoimpl.SizeCache
 }
 
 func (x *Heartbeat) Reset() {
@@ -3110,6 +3159,13 @@ func (x *Heartbeat) GetGpuForeignMemoryMb() []int32 {
 	return nil
 }
 
+func (x *Heartbeat) GetMemBandwidthGbs() float64 {
+	if x != nil {
+		return x.MemBandwidthGbs
+	}
+	return 0
+}
+
 // Provision is the software a node should have: which engines, at which
 // versions. Nothing more.
 //
@@ -3790,7 +3846,14 @@ type EngineProfile struct {
 	Adapters []*LoraAdapter `protobuf:"bytes,12,rep,name=adapters,proto3" json:"adapters,omitempty"`
 	// kv_events has a vLLM engine publish its KV cache events to the agent, for
 	// the router's precise index.
-	KvEvents      bool `protobuf:"varint,13,opt,name=kv_events,json=kvEvents,proto3" json:"kv_events,omitempty"`
+	KvEvents bool `protobuf:"varint,13,opt,name=kv_events,json=kvEvents,proto3" json:"kv_events,omitempty"`
+	// allow_pickle lets the node fetch weights in a pickle format, which run
+	// code when loaded: the catalog's allow_pickle, set on purpose.
+	AllowPickle bool `protobuf:"varint,14,opt,name=allow_pickle,json=allowPickle,proto3" json:"allow_pickle,omitempty"`
+	// model_sha256 is the sha256 the registry published for the file
+	// model_path names, from the catalog's origin: the node refuses a copy
+	// that is not it. Empty when nothing is known to check against.
+	ModelSha256   string `protobuf:"bytes,15,opt,name=model_sha256,json=modelSha256,proto3" json:"model_sha256,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -3916,6 +3979,20 @@ func (x *EngineProfile) GetKvEvents() bool {
 	return false
 }
 
+func (x *EngineProfile) GetAllowPickle() bool {
+	if x != nil {
+		return x.AllowPickle
+	}
+	return false
+}
+
+func (x *EngineProfile) GetModelSha256() string {
+	if x != nil {
+		return x.ModelSha256
+	}
+	return ""
+}
+
 // RemoveWeights deletes cached model files a node no longer needs.
 //
 // The paths are computed by the control plane from the catalog, but the agent
@@ -5180,7 +5257,7 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\x1aA\n" +
 	"\x13EngineVersionsEntry\x12\x10\n" +
 	"\x03key\x18\x01 \x01(\tR\x03key\x12\x14\n" +
-	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\"\xb1\x01\n" +
+	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\"\xdd\x01\n" +
 	"\x04Host\x12\x13\n" +
 	"\x05os_id\x18\x01 \x01(\tR\x04osId\x12\x1d\n" +
 	"\n" +
@@ -5189,7 +5266,8 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"osCodename\x12\x12\n" +
 	"\x04arch\x18\x04 \x01(\tR\x04arch\x12\x1b\n" +
 	"\tcpu_flags\x18\x05 \x03(\tR\bcpuFlags\x12#\n" +
-	"\rnvidia_driver\x18\x06 \x01(\tR\fnvidiaDriver\"u\n" +
+	"\rnvidia_driver\x18\x06 \x01(\tR\fnvidiaDriver\x12*\n" +
+	"\x11mem_bandwidth_gbs\x18\a \x01(\x01R\x0fmemBandwidthGbs\"u\n" +
 	"\aStorage\x12\x12\n" +
 	"\x04path\x18\x01 \x01(\tR\x04path\x12\x1d\n" +
 	"\n" +
@@ -5219,7 +5297,7 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"leaderPort\x12\x1d\n" +
 	"\n" +
 	"profile_fp\x18\x0f \x01(\tR\tprofileFp\x12+\n" +
-	"\acompute\x18\x10 \x01(\v2\x11.llmgw.v1.ComputeR\acompute\"\xca\x06\n" +
+	"\acompute\x18\x10 \x01(\v2\x11.llmgw.v1.ComputeR\acompute\"\xcc\a\n" +
 	"\x03GPU\x12\x14\n" +
 	"\x05index\x18\x01 \x01(\x05R\x05index\x12\x12\n" +
 	"\x04uuid\x18\x02 \x01(\tR\x04uuid\x12\x12\n" +
@@ -5245,7 +5323,13 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"\fcluster_uuid\x18\x13 \x01(\tR\vclusterUuid\x12\x1b\n" +
 	"\tclique_id\x18\x14 \x01(\tR\bcliqueId\x12)\n" +
 	"\x10fabric_bandwidth\x18\x15 \x01(\tR\x0ffabricBandwidth\x12%\n" +
-	"\x03mig\x18\x16 \x01(\v2\x13.llmgw.v1.MIGDeviceR\x03mig\x1a;\n" +
+	"\x03mig\x18\x16 \x01(\v2\x13.llmgw.v1.MIGDeviceR\x03mig\x12\x19\n" +
+	"\bpcie_gen\x18\x17 \x01(\x05R\apcieGen\x12 \n" +
+	"\fpcie_gpu_gen\x18\x18 \x01(\x05R\n" +
+	"pcieGpuGen\x12\x1d\n" +
+	"\n" +
+	"pcie_width\x18\x19 \x01(\x05R\tpcieWidth\x12$\n" +
+	"\x0epcie_width_max\x18\x1a \x01(\x05R\fpcieWidthMax\x1a;\n" +
 	"\rNicPathsEntry\x12\x10\n" +
 	"\x03key\x18\x01 \x01(\tR\x03key\x12\x14\n" +
 	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\"\x84\x02\n" +
@@ -5361,7 +5445,7 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"\x06status\x18\x03 \x01(\tR\x06status\x12!\n" +
 	"\fcluster_uuid\x18\x04 \x01(\tR\vclusterUuid\x12\x1b\n" +
 	"\tclique_id\x18\x05 \x01(\tR\bcliqueId\x12\x1c\n" +
-	"\tbandwidth\x18\x06 \x01(\tR\tbandwidth\"\xa9\a\n" +
+	"\tbandwidth\x18\x06 \x01(\tR\tbandwidth\"\xd5\a\n" +
 	"\tHeartbeat\x12\x17\n" +
 	"\anode_id\x18\x01 \x01(\tR\x06nodeId\x12+\n" +
 	"\x12gpu_memory_used_mb\x18\x02 \x03(\x05R\x0fgpuMemoryUsedMb\x12!\n" +
@@ -5383,7 +5467,8 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"gpu_fabric\x18\x10 \x03(\v2\x18.llmgw.v1.GPUFabricStateR\tgpuFabric\x12\"\n" +
 	"\x04imex\x18\x11 \x01(\v2\x0e.llmgw.v1.IMEXR\x04imex\x12\x1b\n" +
 	"\tcpu_count\x18\x12 \x01(\x05R\bcpuCount\x121\n" +
-	"\x15gpu_foreign_memory_mb\x18\x13 \x03(\x05R\x12gpuForeignMemoryMb\x1aA\n" +
+	"\x15gpu_foreign_memory_mb\x18\x13 \x03(\x05R\x12gpuForeignMemoryMb\x12*\n" +
+	"\x11mem_bandwidth_gbs\x18\x14 \x01(\x01R\x0fmemBandwidthGbs\x1aA\n" +
 	"\x13EngineVersionsEntry\x12\x10\n" +
 	"\x03key\x18\x01 \x01(\tR\x03key\x12\x14\n" +
 	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\";\n" +
@@ -5462,7 +5547,7 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	"profile_fp\x18\x0f \x01(\tR\tprofileFp\x12\x17\n" +
 	"\aapi_key\x18\x10 \x01(\tR\x06apiKey\x12\x1f\n" +
 	"\vcpu_threads\x18\x11 \x01(\x05R\n" +
-	"cpuThreads\"\xcd\x03\n" +
+	"cpuThreads\"\x93\x04\n" +
 	"\rEngineProfile\x12\x12\n" +
 	"\x04name\x18\x01 \x01(\tR\x04name\x12\x16\n" +
 	"\x06engine\x18\x02 \x01(\tR\x06engine\x12\x1b\n" +
@@ -5478,7 +5563,9 @@ const file_llmgw_v1_agent_proto_rawDesc = "" +
 	" \x01(\tR\tmodelPath\x12*\n" +
 	"\x11served_model_name\x18\v \x01(\tR\x0fservedModelName\x121\n" +
 	"\badapters\x18\f \x03(\v2\x15.llmgw.v1.LoraAdapterR\badapters\x12\x1b\n" +
-	"\tkv_events\x18\r \x01(\bR\bkvEvents\x1a6\n" +
+	"\tkv_events\x18\r \x01(\bR\bkvEvents\x12!\n" +
+	"\fallow_pickle\x18\x0e \x01(\bR\vallowPickle\x12!\n" +
+	"\fmodel_sha256\x18\x0f \x01(\tR\vmodelSha256\x1a6\n" +
 	"\bEnvEntry\x12\x10\n" +
 	"\x03key\x18\x01 \x01(\tR\x03key\x12\x14\n" +
 	"\x05value\x18\x02 \x01(\tR\x05value:\x028\x01\"%\n" +

api/proto/llmgw/v1/agent.proto

@@ -238,6 +238,9 @@ message Host {
   // nvidia_driver is the driver version, empty when there is none. A card
   // without a driver is not a GPU anything can use.
   string nvidia_driver = 6;
+  // mem_bandwidth_gbs is how fast the memory reads, in GB/s, measured when
+  // the agent started: what decides a model's speed on the CPU. 0 unknown.
+  double mem_bandwidth_gbs = 7;
 }
 
 // Storage is one filesystem a node keeps weights on.
@@ -334,6 +337,13 @@ message GPU {
   // memory the instance's share; utilization_percent stays zero, because no
   // driver measures it per instance.
   MIGDevice mig = 22;
+  // How the card is linked to its host: the fastest generation card and
+  // slot allow together, the card's own fastest, and the lanes in use and
+  // the card's most. Zero when the driver did not say.
+  int32 pcie_gen = 23;
+  int32 pcie_gpu_gen = 24;
+  int32 pcie_width = 25;
+  int32 pcie_width_max = 26;
 }
 
 // MIGDevice is which card a MIG instance is carved from, and how.
@@ -588,6 +598,11 @@ message Heartbeat {
   // is not handed out. Empty from an agent that does not measure it, or from
   // one that could not this time.
   repeated int32 gpu_foreign_memory_mb = 19;
+
+  // mem_bandwidth_gbs is how fast the node's memory reads, in GB/s, once
+  // the agent has measured it — in the background after it starts, so a
+  // registration usually has none yet. 0 means not measured.
+  double mem_bandwidth_gbs = 20;
 }
 
 // Provision is the software a node should have: which engines, at which
@@ -749,6 +764,13 @@ message EngineProfile {
   // kv_events has a vLLM engine publish its KV cache events to the agent, for
   // the router's precise index.
   bool kv_events = 13;
+  // allow_pickle lets the node fetch weights in a pickle format, which run
+  // code when loaded: the catalog's allow_pickle, set on purpose.
+  bool allow_pickle = 14;
+  // model_sha256 is the sha256 the registry published for the file
+  // model_path names, from the catalog's origin: the node refuses a copy
+  // that is not it. Empty when nothing is known to check against.
+  string model_sha256 = 15;
 }
 
 // RemoveWeights deletes cached model files a node no longer needs.

cmd/llmgw-kb/main.go

@@ -331,6 +331,8 @@ hidden files, version control folders and Office lock files are not.`,
 	f.BoolVar(&o.Delete, "delete", false, "remove documents this machine sent whose files are gone")
 	f.BoolVar(&o.Retry, "retry", false, "read again files skipped before")
 	f.IntVar(&o.Workers, "workers", 4, "files read and sent at once")
+	f.BoolVar(&o.EmbedHere, "embed-here", false,
+		"embed on this machine and send the vectors, even to a gateway that embeds text it is sent")
 	f.StringVar(&ocr, "ocr-languages", "tur+eng", "Tesseract's languages for images and scanned pages")
 	f.Int64Var(&maxMiB, "max-size", 256, "skip files larger than this many MiB")
 	f.BoolVarP(&verbose, "verbose", "v", false, "list unchanged files too")

deploy/systemd/llmgw-agent.service

@@ -2,6 +2,9 @@
 Description=llmgw node agent
 After=network-online.target
 Wants=network-online.target
+# Never given up on: a new release that fails its first starts, or an upgrade
+# that restarts it twice in a minute, would otherwise leave the node off.
+StartLimitIntervalSec=0
 
 [Service]
 ExecStart=/usr/local/bin/llmgw agent --config /etc/llmgw/agent.yaml

docs/client-api.openapi.json

@@ -2890,6 +2890,10 @@
           "writable": {
             "type": "boolean",
             "description": "Writable is whether this caller may add and remove documents."
+          },
+          "server_embeds": {
+            "type": "boolean",
+            "description": "ServerEmbeds says a document may be sent as text alone: the gateway embeds its chunks, as the caller, with the collection's model."
           }
         }
       },

docs/clients.md

@@ -579,6 +579,15 @@ claude mcp add --transport http llmgw https://llm.example.com/mcp \
   --header "Authorization: Bearer $LLMGW_API_KEY"
 ```
 
+**Your company's tools.** Where an administrator has registered the
+company's own MCP servers (Jira, a file server, a database) and your key is
+granted their tools, the same `/mcp` lists them too, each as `server.tool`
+(`jira.search`). Give your agent only llmgw's `/mcp` and your key: the
+servers' own credentials stay with llmgw. A tool your key is not granted is
+not listed, and calling it by name is refused. Each call is in the audit
+log under your key: which tool, the size of what was sent, how it ended and
+how long it took, never what it said.
+
 ### Licences you leave out
 
 A model's licence is in `/v1/models` (`license`: its `id`, `name`, whether

docs/console.md

@@ -2,8 +2,8 @@
 
 `sudo llmgw`, with nothing after it, on a machine llmgw runs on. On a machine
 with nothing installed it opens the setup screens; on a control plane, the
-console described here; on a node, the node's own console, which edits
-`agent.yaml`. Everything on these screens can also be done by command — each
+console described here; on a node, the node's own console, which shows
+what runs on that machine and edits `agent.yaml`. Everything on these screens can also be done by command — each
 screen says which — so a script never needs them and a person never needs
 to remember the commands.
 
@@ -173,6 +173,23 @@ search…** as an administrator, or **Delete…** it. People
 fill collections from their own machines with `llmgw-kb`
 ([knowledge.md](knowledge.md)). Off on a SQLite store, and says why.
 
+**MCP servers** lists the company's own MCP servers that agents reach through
+the gateway's `/mcp`, their tools named `server.tool`: whether each is on,
+who has been granted its tools, its rate per caller, the names of the
+credentials it is sent (never their values) and its address. **A** adds one:
+its name, which is its tools' prefix, its address, and a bearer token or
+another header, kept sealed in the store. On a row: **Test, and list its
+tools**, with its credential, as a call would; **Grant its tools to…** a
+team, project, organization, person or key — all of them, `jira.*`, or some
+by name — beside whatever else that level is granted, and saying when a
+level above keeps them out of reach; **Revoke** a grant;
+**Change…** its address, timeout or rate; **Replace its credential…**;
+**Turn off** (its tools are listed nowhere and every call refused) or on;
+**Remove…**. A server's tools are seen nowhere until granted. The screen
+also says how a person points an agent at the gateway, with a key of their
+own from `/profile/keys`. `llmgw ctl mcp` does the same from a shell, and
+the web page **MCP servers** (`/admin/mcp`, administrators only) in a browser.
+
 **Mirror** is what the model mirror holds, one row for each version of each
 model — a file, or the set of files a model of several is: shards, a vision
 projector, a config and tokenizer — with how far its download has got and
@@ -246,6 +263,28 @@ long a key made there may live, and is the expiry of one made without any
 Limits are requests and tokens a minute, a budget per day or month, and the
 models allowed. Each level only narrows what is above it.
 
+**Sign-in** — how people get in besides a password kept here: single
+sign-on, Active Directory and provisioning, each on or off, with the
+directory's last sync (how many people, accounts kept in step, suspended,
+reinstated).
+- **E** sets up Entra ID. Give the tenant ID, the client ID and secret,
+  and the groups for administrators and operators. A provider other than
+  Entra takes its issuer URL in place of the tenant. The form shows the
+  redirect address to register.
+- **D** sets up Active Directory: the servers, where people are, the
+  service account and its password, the domain's CA certificate as a PEM
+  file on this machine, the group whose members may sign in, and groups
+  for roles and teams.
+- Before it is kept, the directory is tried from the control plane: each
+  server reached and bound, how many people may sign in, how many are in
+  each group. If any step fails, nothing is kept and the steps are shown.
+  **T** tries the settings in force.
+- On the provisioning row, Enter makes a SCIM token, shown once.
+- The password, the client secret and the token are kept in the store,
+  sealed by the master key when one is set. The settings name them as
+  `store:auth/…`, so each control plane has them with no file put on it.
+  The CA is written into the settings themselves.
+
 **Guardrails…** on a row lists the guardrail policies server.yaml defines.
 Each policy is marked in one of three ways:
 
@@ -335,5 +374,18 @@ to restart it.
 
 ## The node's console
 
-On a node, `sudo llmgw` opens `agent.yaml` in the same settings view, and the
-manual. The cluster is watched and changed from a control plane.
+On a node, `sudo llmgw` opens on **Overview**: what this machine is doing, read
+on the machine itself, so it works without an admin token and while the control
+plane is out of reach. Refreshed every three seconds, it shows
+
+- llmgw-agent's state and since when, and the version of llmgw;
+- each control plane the agent dials, from `agent.yaml` and the list the
+  leader last sent, and whether it can be reached;
+- each GPU: how busy, its memory, its heat, and the models on it;
+- the engines running here, from the agent's own records: replica, model,
+  engine, GPUs, port, whether the process is still there, and for how long;
+- the free space where weights and engines are kept;
+- the agent's warnings and errors of the last hour.
+
+Below it, `agent.yaml` in the same settings view, and the manual. The cluster
+is watched and changed from a control plane.

docs/data.md

@@ -72,7 +72,9 @@ each answer that may be reused, as the client got it, and a hash of the
 request it answers, in the gateway process's memory — never in the store,
 never on disk — for the project's TTL or until pushed out by newer ones
 (`router.cache.max_bytes`), and gone with a restart. Never under a `no_store`
-policy. Forgetting a person does not reach into it; the answers age out by
+policy. A project that reuses answers to similar questions (`--similar`)
+also has each question's last user message embedded, and the vector kept
+beside its answer, in the same memory and for as long. Forgetting a person does not reach into it; the answers age out by
 the TTL. The store keeps only the setting, and a usage record's mark that it
 was answered from the cache.
 

docs/guardrails.md

@@ -91,6 +91,21 @@ guard:
   value is the same placeholder throughout a request).
 - **`block`** stops it.
 
+**Putting them back.** With `restore: true` in a policy's `input`, the
+values a request had redacted are put back in its answer: the model reads
+"write to [PERSON_1] at [EMAIL_1]", the client reads the name and address
+it sent. Streamed answers too — a placeholder split across two events is
+held until it is whole. Only that request's own values, only into its
+answer; the map is kept in memory for the request and nowhere else. The
+output rules then read the answer as the client will, so a policy that
+redacts personal data in answers still does.
+
+```yaml
+input:
+  pii: {email: redact, phone: redact}
+  restore: true
+```
+
 **Shapes.**
 
 - `system_prompt` is put first.
@@ -258,6 +273,47 @@ themselves.
     context rather than overflowing it and going unjudged.
 - **Cache:** the same text is not asked about twice within five minutes.
 
+## An outside service
+
+A site required to use a particular guardrail — Azure Content Safety,
+Lakera Guard, NeMo Guardrails, a classifier of its own — names it in a
+policy's `services`. It is asked over HTTP beside the patterns and before
+the judge; its "unsafe" blocks or flags like theirs, and a service that does
+not answer is what the policy's `fail` says.
+
+```yaml
+policies:
+  strict:
+    fail: closed
+    services:
+      - name: lakera
+        url: https://api.lakera.ai/v2/guard
+        header_files: {Authorization: /etc/llmgw/secrets/lakera}   # "Bearer …", read each call
+        body: '{"messages": [{"role": "user", "content": {{json .Text}}}]}'
+        blocked: flagged                 # where the answer says unsafe
+        reason: breakdown.0.detector_type
+        on: both                         # input, output or both
+        action: block                    # or flag
+        timeout: 2s
+```
+
+`body` is a template given `.Text` (`{{json .Text}}` writes it as a JSON
+string; empty sends `{"input": …}`). `blocked` and `reason` are dotted paths
+into the JSON answer, numbers for list items; true, a number above zero, a
+non-empty list or a string other than "false" is unsafe. On input the
+service reads the latest user turn as the model will, with what `redact`
+took out still out; on output the whole answer, once, at its end, as the
+client reads it — with `restore`, the values put back. Being at the end, a
+service can stop a streamed answer only where it is held back
+(`stream: buffer_all`): released a sentence at a time, the client has read
+it by then, and what the service finds ends the stream with
+`content_filter`, flags it and is recorded. The rule recorded is
+`service:<name>:<reason>`. The service is told the text only, never who
+sent it. Under `fail: open`, the default, a service that cannot be asked
+lets the text through — and a caller can make it fail, sending what it
+refuses to read; give `fail: closed` where the service must decide. Of an
+answer asked for with `n` above 1, the service reads the first.
+
 ## Where a policy applies
 
 `guard.default` applies everywhere. Others are attached to a part of the

docs/install.md

@@ -152,9 +152,9 @@ That is the whole step. In order, it:
    `nvidia-smi` finds any, on CPU otherwise — and waits for it to install its
    engine
 9. closes llmgw's internal ports to everything but the cluster's networks
-10. fetches Qwen3Guard-Gen 0.6B, the guardrails' judge, and runs two
-    replicas on the CPUs of nodes with room — this one, or the first that
-    join ([guardrails.md](guardrails.md#a-judge-model) has one on a GPU too)
+10. fetches Qwen3Guard-Gen 0.6B, the guardrails' judge, and runs it on
+    CPUs: one replica on up to four cores when this machine is the only
+    node, two on two cores each on the nodes of a larger cluster ([guardrails.md](guardrails.md#a-judge-model) has one on a GPU too)
 11. fetches Qwen2.5 0.5B into the mirror and serves it on this node, so the
     first thing anyone opens `/chat` to find is a model that answers. A
     machine without room for it is told so within two minutes, and why.
@@ -187,15 +187,43 @@ demonstration one:
 | Requests | every key limited (60 a minute, 200 000 tokens a minute) and priced, so budgets bind |
 | Guardrails | the `baseline` policy on every request: secrets in prompts and answers refused, card numbers masked, injection attempts recorded, and the judge refusing violence, crime, weapons, child abuse, privacy violations, hate, self-harm and sexual content, in prompts and answers |
 
-The judge runs as two replicas, each on a CPU — about half a second for a
-short text on any CPU with AVX2 — and reads a streamed answer every 600
-characters. The policy fails **closed**: a request the judge cannot read
-within 5 seconds is refused with 503 rather than served unjudged, and
-`judge_unavailable` goes to the notification webhooks. Two replicas are what
-make that bearable; on one small machine, or a VM without AVX2 (see
+The judge runs on CPUs. A judgment of about 280 tokens took 2.3 s on four
+cores, 4.2 s on two and 8.0 s on one (a 4-core VM). It also reads a
+streamed answer every 600 characters. The policy fails **closed**: a request
+the judge cannot read within 5 seconds is refused with 503 rather than
+served unjudged, and `judge_unavailable` goes to the notification webhooks.
+So a judge gets cores of its own: on one machine one replica on up to four,
+and on a larger cluster two replicas of two cores each, spread over its nodes
+so that losing one leaves the other. On a machine of fewer than four cores,
+a busy one, or a VM without AVX2 (see
 [step 6](#6-setting-the-nodes-cpu-model-if-it-is-a-vm)), the judge is the
-first thing to fail, so `fail: open` — serve it, recorded as flagged — or
-`--no-guard-model` is the choice there. Defamation, specialized advice,
+first thing to fail. The choices there are a longer `latency_budget`,
+`fail: open` (serve the request, recorded as flagged), the judge on a GPU,
+or `--no-guard-model`.
+
+init times the judge once it is up. If a judgment takes more than half the
+wait, or more than the wait when several come at once, it says so before the
+next steps, with what to do. The wait itself is not changed without being
+asked. `llmgw ctl guard judge check` does the same at any time:
+
+```
+qwen3guard-0.6b, 2 replica(s) ready, a request waits 5.0 s for it
+  alone:    2.4, 2.3, 2.3 s
+  4 at once: slowest 6.1 s; about 0.7 judgments a second, so about 0.3 requests a second with short answers
+tight: a busy moment passes the budget
+```
+
+In a three-machine install the judges are better on machines of their own.
+On a 4-core control plane that was also a node, 38 of 60 requests under load
+were refused for want of a judgment. With the judges on a node of their own
+(4 cores, two judges of two cores each), 2 were refused. The setup screen asks
+for up to two **judge machines** after the store's two, or give
+`--judge-node user@host` to `server init`, once for each. Each is added as a
+node labelled `llmgw.role: judge`, and the judge's profile selects that
+label, so the judges run only there and nothing else does. Four cores and
+8 GB are enough for two judges.
+
+Defamation, specialized advice,
 intellectual property and elections are left out of what it refuses: they
 catch too much ordinary work. [guardrails.md](guardrails.md) has the rest.
 
@@ -363,7 +391,11 @@ by itself. Three things are worth knowing before you edit it:
 - `default_rpm`, `default_tpm` and `default_price` are what make limits and
   budgets mean anything. Without a price every request costs zero and a budget
   never binds; without the defaults, a project created without limits is
-  metered by nothing at all.
+  metered by nothing at all. A price may set `cached_per_1k` beside
+  `prompt_per_1k`: the prompt tokens the engine or provider read from its
+  cache (the answer's `cached_tokens`) are charged at it, the rest at the
+  prompt rate. A provider that bills cached reads at a tenth is
+  `{prompt_per_1k: 2500, cached_per_1k: 250, completion_per_1k: 10000}`.
 - `control.enabled: true` is what makes this a control plane while its catalog
   is empty. Without it, a file with no models is refused as having nothing to
   serve.
@@ -671,6 +703,7 @@ Nothing to do: the agent installs them once the node joins, under
 | vLLM | nodes with an NVIDIA GPU it can run on | a Python environment built by uv from PyPI, about 8 GB |
 | SGLang | only when you ask for it | the same way as vLLM |
 | TensorRT-LLM | only nodes where you installed it | not installed by llmgw: see [TensorRT-LLM, which you bring](#tensorrt-llm-which-you-bring) |
+| Strata | only when you ask for it (`engines: {strata: "0.2.7"}`) | its source, pinned by digest, in a Python environment, and its prebuilt engine for CUDA 13 (driver 580+) or CUDA 12.9 (Pascal to Ada, driver 575+); see [Strata](#strata-a-large-model-of-experts-on-one-card) |
 
 vLLM is resolved as PyPI stood a day after that vLLM was published, so every
 node gets the same dependencies whenever it is built, and installed with
@@ -713,6 +746,45 @@ you installed yourself on a node, name its path in that node's `agent.yaml`
 (`engines.llamacpp.bin`, `engines.vllm.bin`, `engines.sglang.python`,
 `engines.trtllm.python`): the agent then installs none of its own beside it.
 
+#### Strata: a large model of experts on one card
+
+Strata runs a few mixture-of-experts models — Qwen3.8-Flash-Next (125B) and its
+Swift, Coder, Unsloth, Gyro and NVFP4 versions, Qwen3.6-35B-A3B, DeepSeek
+V4.1-Flash — with the experts in the node's RAM and the rest on one card of 12
+GB or more. Where it is installed, the plan offers it for a repository of one
+of those families:
+
+```
+llmgw ctl model plan ISTA-DASLab/Qwen3.8-Flash-Next-GSQ-RCO-GGUF
+llmgw ctl model serve ISTA-DASLab/Qwen3.8-Flash-Next-GSQ-RCO-GGUF \
+  --file Qwen3.8-Flash-Next-GSQ-RCO-IQ2_XS-00001-of-00002.gguf --engine strata
+```
+
+The Hugging Face explorer shows the same ("1× … with Strata, N GB of RAM"),
+and the mirror's serve form serves such a version on Strata.
+
+The mirror page's **Strata** tab lists every family and size Strata runs, with
+what each downloads and keeps in RAM and where it would run here:
+
+- **Fetch into the mirror**, for the GGUF families: the size's files, checked
+  against Hugging Face's checksums; the version's serve form then serves it on
+  Strata.
+- **Serve**, for the packs Strata fetches itself — the NVFP4 packs
+  (`Maximilian228/Qwen3.8-Flash-Next-NVFP4-GPTQ-Strata` and its NVIDIA
+  sibling, NVIDIA's FP4-Local) and DeepSeek V4.1: the model is added with the
+  repository as its source, and its first start fetches tens of gigabytes onto
+  the node, each file pinned and checked by Strata, before preparing it.
+  `ctl model serve` does the same for these repositories.
+
+Repositories of architecture `strata-ple` that Strata 0.2.7 does not list —
+community packs such as `…-Q8_0-Strata` — are named as such in the explorer:
+Strata's setup refuses them, and llama.cpp cannot read them. A Strata profile
+says its family and size (`--family qwen --size IQ2_XS`), which the catalog
+checks against what Strata runs, and reserves the RAM the size keeps its experts
+in (48 GB and the engine's 4 for IQ2_XS) unless it says `min_memory_gb`. Its
+first start prepares the model on the node, which takes minutes, and fetches a
+draft layer of about 5 GB from the internet.
+
 #### Choosing a node's vLLM build
 
 Which build a GPU node installs is chosen on the cluster page, in the **vLLM
@@ -844,6 +916,45 @@ Nothing to do here if you built the mirror in step 3 — the agent fetches what
 model's `source` names, and that source is your mirror. This section is for the
 arrangements where the files are already on the machine.
 
+**Weights in a pickle format are refused.** `.bin`, `.pt`, `.pth`, `.ckpt` and
+`.pkl` are Python pickles, and loading one runs whatever it holds, as the
+engine's user, on the node — which is how the malicious models found on Hugging
+Face work. A model whose source is one, or a mirror version holding one, is
+refused when it is added and by the node before it fetches anything; vLLM and
+SGLang given a model by its Hugging Face id read only its safetensors. Take the
+repository's safetensors or GGUF. A model that has no other form, and whose
+files were checked, can say so:
+
+```yaml
+- name: triposr
+  source: http://mirror:8081/triposr/<rev>/model.ckpt
+  allow_pickle: true
+```
+
+A local path is judged by its name as any source is; a local directory is
+not looked into. What an engine downloads itself by a Hugging Face id, past
+the node — an adapter given by its id, a TensorRT-LLM model's — is refused
+when the model is added, unless it says `allow_pickle`: mirror its
+safetensors and give that instead.
+
+**Weights are pinned to a commit and checked.** A model added with
+`ctl model add`, the API or the console, whose weights come from Hugging Face,
+is pinned to the commit the repository is at when it is added:
+
+- `hf:org/repo/file` and a `…/resolve/main/…` URL become that commit's URL;
+- a repository vLLM or SGLang downloads itself is given `--revision`;
+- the sha256 Hugging Face published for each file goes in the model's origin
+  (its definition, `GET /api/v1/models/NAME`, shows it).
+
+A node then refuses a copy of the file that is not it, naming both checksums,
+and deletes it; a cached copy is checked once and its checksum kept beside it.
+The mirror does the same for a model `ctl model serve` fetches, and
+`llmgw mirror add` for a Hugging Face URL (`--sha256` for any other). A new
+upload to the repository reaches the cluster only through `ctl model update`,
+which says what changed. Not pinned: models declared in the cluster's settings,
+which are not added this way, and a vLLM model whose arguments already say
+`--revision` keeps that one.
+
 Put them where the node can read them. `scp`, a shared filesystem, or the
 engine's own downloader are all valid, and which you want depends on how many
 nodes you have.
@@ -1002,6 +1113,27 @@ A node with no location is placed as before, as a rack of its own.
 See [facility-aware-placement.md](facility-aware-placement.md) for power caps
 and holds.
 
+### A card in the wrong slot
+
+An x16 card in a slot wired x8 or x4, behind a riser, or in a slot of an
+older PCIe generation than the card's, links slower than it was built to and
+works otherwise. A model on the card still decodes at the card's own memory
+speed, but it loads slower, a replica split over several cards by PCIe is
+slower, and so is anything that spills to the host. Each card's agent reads
+how its link stands — the fastest generation card and slot allow together,
+and the lanes in use — against what the card could do, and the node says so
+among its warnings (the dashboard, the console's Nodes, `llmgw doctor`):
+
+```
+GPU 1 (NVIDIA H100 80GB HBM3) linked at x8 of its x16 lanes: 31.5 GB/s where it
+could have 63.0. Check the slot (wired fewer lanes, or an older generation), a
+riser, or the BIOS's PCIe setting
+```
+
+The generation a card reports now drops while it idles, to save power; what is
+compared is the fastest it may reach, which does not. `lspci -vv -s BUS-ID`
+shows the same: `LnkCap` is the card's, `LnkSta` the link's.
+
 ## 6. Setting the node's CPU model, if it is a VM
 
 Proxmox defaults a VM to `kvm64`, which hides AVX, AVX2, FMA and even SSE4.2
@@ -1319,6 +1451,26 @@ catalog, and a key rotated in the file is used within seconds. A model whose key
 file cannot be read is not offered. Everything else applies as to any model:
 prices and budgets, rate limits, usage records, and key allowlists.
 
+A provider's limits are per key. With several keys, one answering 429 need not
+hold up the model: give them all, each with an optional weight (its share
+against the others'), in place of `api_key_file`:
+
+```yaml
+  external:
+    url: https://api.openai.com
+    model: gpt-4o-mini
+    api_key_files:
+      - {file: /etc/llmgw/secrets/openai-1.key, weight: 2}
+      - {file: /etc/llmgw/secrets/openai-2.key}
+```
+
+Each key is an endpoint of its own, `external:cloud-mini#1`, `#2`. A key that
+answers 429 is passed over while its breaker is open, and the request goes to
+another. One that answers 401 (revoked, expired, mistyped) is passed over too,
+and `external_key_refused` goes to the notification webhooks, naming the
+endpoint and never the key. The usage records say which key answered by the
+same name. A key whose file cannot be read is left out, and the others stay.
+
 **Its prompts leave the cluster.** Decide who may send them: a key or project
 whose allowlist leaves the external model out cannot reach it, as a fallback or
 by name. The cluster page and `ctl models` mark it `external`.
@@ -1535,6 +1687,79 @@ Not yet: models declared in server.yaml cannot name a peer's model as a
 fallback (the catalog in the file is checked before the peers are read), and
 a peer behind a private CA needs that CA in the system's trust store.
 
+### Stopping a model, and removing one with its files
+
+```
+llmgw ctl model stop qwen-7b             # none of its replicas run; it is kept
+llmgw ctl model start qwen-7b            # runs again, scaled as it was
+llmgw ctl model remove qwen-7b           # leaves the catalog; its files stay
+llmgw ctl model remove qwen-7b --purge   # its files on the mirror and the nodes too
+```
+
+- **Stop** keeps the model in the catalog with its files and what it was
+  scaled to; a request for it is told an administrator stopped it. `ctl
+  models` shows it as stopped. A `ctl scale` while it is stopped starts it at
+  that number.
+- **Remove** leaves its files on the mirror and the nodes, for adding it
+  again without fetching it. `ctl weights` lists such files on the nodes.
+- **Remove --purge** deletes every version of it on the mirror (a second
+  mirror follows), its adapters and the weights its last update replaced,
+  and the nodes' copies once its replicas have stopped. What another model
+  uses — a canary's weights, a shared adapter — stays. It cannot be undone:
+  adding it again fetches it again.
+
+The console has the same in a model's menu: Stop… or Start, Remove…, and
+Remove with its files….
+
+### Changing a served model's context
+
+How much one request may use is set when a model is served. To change it
+afterwards:
+
+```
+llmgw ctl model context qwen-7b 32768             # tokens a request
+llmgw ctl model context qwen-7b 32768 --slots 4   # llama.cpp: four at once
+```
+
+The catalog, the engine's arguments (`--ctx-size` and `--parallel` for
+llama.cpp, `--max-model-len` for vLLM, `--context-length` for SGLang) and
+the memory its KV cache takes change together. A context longer than the
+model was trained for is refused, and so is one its cards cannot hold — with
+the figures, so you know how far to go. Its replicas are then started again on
+it, one by one, a new one ready before the old one stops. The console has the
+same under a model's menu, Context length…. A model declared in the cluster's
+settings is changed there (`llmgw ctl config edit`).
+
+### Moving a served model to more cards
+
+How many cards of one node each replica uses can be changed while the model
+is served:
+
+```
+llmgw ctl model gpus qwen3-coder-30b 2              # two cards a replica
+llmgw ctl model gpus llama-70b 4 --profile h100     # the model has several profiles on cards
+llmgw ctl model gpus qwen3-coder-30b 2 --in-place   # no room beside the running replica
+```
+
+vLLM, SGLang and TensorRT-LLM spread the model by tensor parallel (`tp`),
+which needs the count to divide the model's KV heads or be divided by them:
+a model with 8 splits 2, 4, 8 or 16 ways, not 3 or 12. llama.cpp has no
+tensor parallel; it splits the layers over the cards (`gpus_per_node`), and
+a `--tensor-split` written for the old cards is dropped. ComfyUI and Strata
+run on one card. A count no node has is refused, and so is one whose cards
+would not hold the weights and the context — with the figures; fewer cards
+with a long context may need `llmgw ctl model context` first.
+
+Its replicas are then started again on it, each new one ready beside the old
+before the old stops. That needs the cards free beside it: on a node of two
+cards with the model on one, two do not fit until it is gone, and the command
+says so. `--in-place` stops each replica first and starts its replacement on
+the cards it held and the free ones, and the model does not answer while the
+new one loads — a model with several replicas keeps answering on the others.
+A replica spread over several nodes is laid out by hand, with a fabric
+(`nodes`, `gpus_per_node` in the profile). The console has the same under a
+model's menu, GPUs….
+
 ### Trying new weights on some of the traffic first
 
 When a model's repository publishes new weights, `llmgw ctl model update`
@@ -1909,6 +2134,18 @@ So "why did qwen take four minutes to start" is one trace: find `replica start`
 with `llmgw.model` = qwen, and the node's spans beneath it say whether the
 time went to the download, the launch or the engine loading.
 
+An inference request and each `upstream` attempt also carry the
+[OpenTelemetry GenAI conventions](https://opentelemetry.io/docs/specs/semconv/gen-ai/),
+so a tool that reads them — Grafana, Jaeger, Langfuse, Arize Phoenix — shows
+llmgw's calls as model calls without a dashboard made for llmgw:
+`gen_ai.operation.name` (`chat`, `text_completion`, `embeddings`),
+`gen_ai.request.model`, `gen_ai.request.max_tokens`, `temperature` and `top_p`
+when the client set them, `gen_ai.conversation.id` (the session),
+`gen_ai.response.model`, and `gen_ai.usage.input_tokens`, `output_tokens` and
+`cache_read.input_tokens`. On an `upstream` span `gen_ai.provider.name` is the
+engine that answered (`vllm`, `llamacpp`, `external`, …). What was asked and
+what was answered are never in a span.
+
 A node follows the control plane's decision: a start the control plane kept is
 traced on the node whatever the agent's own `sample_ratio`, and one it sampled
 out is not; the agent's ratio decides only for what arrives with no trace, as
@@ -2073,8 +2310,10 @@ llmgw keys cache --project Acme/ml/train --off
 - **Policies still apply:** the limits are checked and the guardrails judge
   the request before the cache is looked in, and the output policy judges a
   reused answer as it would a new one. A request continuing a stored
-  conversation, or under a `no_store` policy, is never answered from the
-  cache nor kept in it.
+  conversation, under a `no_store` policy, or whose redacted values are put
+  back in its answer (`restore: true`) is never answered from the cache nor
+  kept in it: redacted, two callers' requests read the same, and the answer
+  has the first caller's values in it.
 - **What a hit costs:** nothing. It is recorded as a request — status 200,
   the model, the key, the rate limit's count — with no tokens and no cost,
   marked as a cache hit (`llmgw ctl request <id>` says so), so it spends no
@@ -2094,8 +2333,46 @@ router:
     max_entry_bytes: 2097152 # 2 MB
 ```
 
-`llmgw_cache_requests_total{model,result}` counts hits, misses and
-bypasses, `llmgw_cache_bytes` and `llmgw_cache_entries` what is held. The
+### Similar questions
+
+A help desk asked "how do I reset my password" in forty wordings asks the
+model forty times under the exact cache. `--similar` also gives a chat
+question the answer to one like it:
+
+```
+llmgw keys cache --project Acme/support/desk --ttl 24h --similar 0.95
+```
+
+```yaml
+router:
+  cache:
+    embedding_model: bge-m3   # an embedding model in the catalog
+```
+
+- **What is compared:** the last user message, embedded by
+  `router.cache.embedding_model`, against the questions already answered
+  in the same conversation — the same system prompt, the same earlier turns,
+  tools, `response_format` and sampling settings, the same model and
+  project. A like question in another conversation, after a tool's result,
+  or with a picture, a sound or a file in it, is not taken for this one. The exact cache is asked first, and an
+  exact hit embeds nothing.
+- **How alike:** the cosine similarity of the two embeddings, at least the
+  project's `--similar`. 0.95 is strict; below 0.9 different questions start
+  to meet. A question that differs only in a number or a name ("2+2" and
+  "2+3") can be closer than that, so a project whose questions turn on
+  figures should not use it. A question over 2,000 characters is reused only
+  when it is the same.
+- **Said:** `x-llmgw-cache: similar`, with `x-llmgw-cache-similarity`
+  and `Age`. Recorded and charged as a hit. The same rules as a hit decide
+  which answers are reused and kept; guardrails judge the request before.
+- **The embedding** is asked of the model by the gateway on its own account,
+  as a judge is, within 2 seconds; every miss waits for it. Without the
+  model, or when it does not answer, only the same request is reused. The
+  vectors are kept in memory with their answers and counted in
+  `router.cache.max_bytes`.
+
+`llmgw_cache_requests_total{model,result}` counts hits, similar hits, misses
+and bypasses, `llmgw_cache_bytes` and `llmgw_cache_entries` what is held. The
 console has it as **Cache answers…** on a project.
 
 ## Batches
@@ -2204,6 +2481,7 @@ triposr`. What that adds is this entry, and its workflow is built in:
 ```yaml
 - name: triposr
   source: hf:stabilityai/TripoSR/model.ckpt
+  allow_pickle: true               # published as this checkpoint only
   comfyui:
     workflow: triposr              # built in; a model of your own names a JSON file on every control plane
     output: meshes
@@ -2375,8 +2653,37 @@ lost: a standby leads within seconds, Patroni promotes the standby database
 if it was the primary, and the floating address follows whichever leads. The
 mirror's management API answers the three control planes' addresses, not
 only its own machine's, so a standby that comes to lead can still fetch and
-add models. The mirror itself stays on the first machine: while it is down,
-models the nodes already have keep serving, and new ones wait for it.
+add models.
+
+**A second mirror.** The mirror is on the first machine, and without a
+second one, models the nodes already have keep serving while that machine
+is down, and new ones wait for it. With a second, the cluster carries on.
+- **Setting it up:** the screens offer one on either database machine
+  ("A second mirror"); by command, `--second-mirror 1` (or `2`). For an
+  install that has one mirror, run this on the mirror's machine:
+
+  ```
+  sudo llmgw mirror add-peer ubuntu@10.0.0.7 --control-plane 10.0.0.5 --control-plane 10.0.0.6 --control-plane 10.0.0.7
+  ```
+
+  It logs in with root's ssh key on the mirror's machine, so that key must
+  be accepted for the user named on the second machine. When the mirror has
+  a machine of its own, without the control plane, the command cannot change
+  the cluster's settings itself: it prints the `llmgw ctl config set
+  mirror.peers …` to run on a control plane.
+- **Kept in step:** each mirror reads the other every thirty seconds and
+  copies what it lacks, keeping a copy only if its checksum matches.
+  - A model removed from one is removed from the other, even if that one
+    was down at the time and comes back later.
+  - A model added again after it was removed stands on both.
+  - Neither mirror leads.
+- **Control planes:** they name both (`mirror.peers` in the cluster's
+  settings) and send the mirror's management calls to the first that
+  answers.
+- **Nodes:** while the mirror a model's address names is down, a node is
+  given the same file on the other.
+- **Disk:** the second machine needs room for every model, as the first
+  does.
 
 ## Two control planes
 
@@ -2460,6 +2767,89 @@ the same files and keys as `locales/en/`, and its `_meta.*` entries saying how
 it writes numbers and dates. The tests refuse a catalogue that lacks a key a
 page uses.
 
+## The company's MCP servers
+
+llmgw's `/mcp` can serve the company's own MCP servers beside its own tools.
+Each server, a ticket system, a file server or a database, is registered once.
+Its credentials stay on the control planes, and people's agents are given only
+`/mcp` and their llmgw key.
+
+```
+llmgw ctl mcp add jira --url https://jira.internal/mcp \
+    --description "Acme Jira" --secret-file Authorization=/root/jira-token
+llmgw ctl mcp test jira          # its tools, asked with its credentials
+llmgw keys limits --scope team --id Acme/support --tools 'jira.*'
+```
+
+- **Credentials:**
+  - `--secret-file NAME=FILE` reads a header's value once and keeps it in
+    the store, sealed by the master key, so no file has to be on each
+    control plane.
+  - `--header-ref NAME=REF` reads it at each call from a file, `env:`,
+    `vault:` or `store:` instead.
+  - `--header NAME=VALUE` is for what is not secret.
+- **Who may call what:** tools are named `server.tool` and granted as
+  patterns (`jira.*`, `db.query`) at any level of the tenancy tree, as
+  models are.
+  - A level that names any narrows what is above it: a tool is seen where
+    every level above that names tools names it too. A team under an
+    organization that names `hr.*` sees no `jira.*` whatever the team is
+    given, until the organization names it as well.
+  - Unlike models, **none granted anywhere is none**: a tool reaches into a
+    company system, so it is granted, never assumed.
+  - `keys limits --tools` writes a level's list whole, every server's
+    together; an empty list (`--tools ''`) closes the level to every tool.
+    The console's **MCP servers** screen and the `/admin/mcp` page grant
+    and take back one server's tools: a level given its first list starts
+    from the nearest list above it, so it keeps what it saw; one left
+    naming none goes back to naming none, or stays closed when a level
+    above names tools, so taking one server away opens it to no other. They
+    say when a level above keeps the granted tools out of reach.
+- **The server is told who calls:** `X-Llmgw-Key`, and `X-Llmgw-User` and
+  `X-Llmgw-Project` where there are some. It is called with llmgw's
+  credentials, never the caller's key.
+- **Bounds:** a call has 60 seconds (`--timeout`) and an answer 4 MB. A
+  server's progress is passed on to a client that takes a stream. `--rate N`
+  allows each caller N calls a minute to a server's tools.
+- **Guardrails, both ways:** the caller's policies read a tool's answer as
+  the prompt it becomes.
+  - An instruction planted in a ticket is caught as a pasted one would be
+    (`injection: block`).
+  - Personal data is redacted or refused as the policy says. A refused
+    answer does not reach the agent.
+  - The arguments are read before they leave, so a secret pasted into one
+    does not reach the company system.
+- **A server that keeps failing:** five calls failing in a row take a server
+  out for a minute. Its tools leave the list, and a call is answered at once.
+- **Record:** every call is in `llmgw ctl audit`, with its arguments' size
+  and a digest, never their text. `llmgw_mcp_tool_calls_total` and
+  `llmgw_mcp_tool_call_seconds` count them by server, tool and outcome.
+- **Changes:** a server added, changed or removed on one control plane is
+  served by every one within half a minute; its tool list is read again
+  every five minutes. `--disabled` keeps a server but serves none of its
+  tools.
+
+**This cluster's own, read only.** `llmgw ctl mcp add llmgw --url
+llmgw:admin` registers the cluster itself as a server: tools that say what
+`llmgw ctl` does, and change nothing. It is answered in the control plane's
+own process, with no address and no token to give.
+
+| Tool | Says |
+|---|---|
+| `llmgw.cluster_status` | control planes, store, nodes, models against what they asked for, GPUs, what is unhealthy |
+| `llmgw.list_nodes` | each node's state, GPUs, load, fabrics, agent version and engines |
+| `llmgw.list_models` | each model's replicas ready against wanted, profiles, why one is parked |
+| `llmgw.list_replicas` | each replica's shards: node, GPUs, state (`model` for one model's) |
+| `llmgw.explain_placement` | why a model is not placed, node by node |
+| `llmgw.node_logs` | a node's last agent log lines, or an engine's (`source`) |
+
+Grant it as any other: `llmgw keys limits --scope key --id KEY-ID --tools
+'llmgw.*'`. It is the same as an administrator's view, so grant it to the
+people who would have `ctl`.
+
+Servers over HTTP only for now (the streamable HTTP transport). A server
+that runs as a local process (stdio) is planned.
+
 ## Single sign-on
 
 People can sign in through your identity provider — Keycloak, Entra ID,
@@ -2467,8 +2857,10 @@ Google, Okta, Authentik, anything that speaks OpenID Connect.
 
 1. Register a client there with the redirect address
    `https://<gateway>/login/oidc/callback`.
-2. Put its secret in a file only root reads.
-3. Add to `server.yaml`:
+2. Put its secret in a file the llmgw user reads, on every control plane.
+3. Add this to the cluster's settings with `llmgw ctl config edit`. On a
+   cluster with a store, `auth` is the cluster's: the same block in
+   `server.yaml` is not read, and the log says so.
 
 ```yaml
 auth:
@@ -2517,6 +2909,99 @@ and point it at `https://<gateway>/scim/v2` with that token as the bearer.
   join and leave them. Membership in a group is removed when someone leaves
   it.
 
+### Entra ID
+
+The console sets this up: `sudo llmgw`, People → Sign-in, **E**. What
+follows is what it writes, and what to do in Entra.
+
+Entra ID is an OpenID Connect provider like the others, with two things to
+set in the app registration:
+
+1. **Redirect URI:** under Authentication, add a Web platform with
+   `https://<gateway>/login/oidc/callback`. The issuer is
+   `https://login.microsoftonline.com/<tenant-id>/v2.0`.
+2. **Groups in the token:** under Token configuration, add a groups claim.
+   Choose **Groups assigned to the application**, and assign the groups you
+   map in `roles` and `memberships` to the enterprise application. Entra
+   sends groups by object id unless you choose to emit names
+   (`sAMAccountName` for groups synced from AD), so write them the same way
+   in the mapping.
+
+Entra leaves the groups out of the token for someone in more than 200 of
+them and sends a pointer to Graph instead. llmgw then keeps that person's
+role and memberships as they were, rather than reading it as no groups, and
+logs an error saying so. "Groups assigned to the application" avoids this.
+So does SCIM below, which Entra also speaks: in the enterprise application
+under Provisioning, set the tenant URL to `https://<gateway>/scim/v2` and
+the secret token to the contents of `auth.scim.token_file`.
+
+## Active Directory
+
+With an on-premises Active Directory, people sign in on the gateway's own
+form with their AD username (`ada`, `CORP\ada`, `ada@corp.example`) and
+password. The gateway checks them with the domain controllers over LDAPS.
+
+The console sets this up and tries it first: `sudo llmgw`, People →
+Sign-in, **D**. It keeps the service account's password in the store
+(`bind_password_file: store:auth/ldap-bind`) and writes the CA into the
+settings (`ca:`), so nothing has to be copied to each control plane.
+By hand it is this block in the cluster's settings (`llmgw ctl config
+edit`), where files it names must then be on every control plane:
+
+```yaml
+auth:
+  enabled: true
+  ldap:
+    urls: [ldaps://dc1.corp.example, ldaps://dc2.corp.example]   # tried in order
+    ca_file: /etc/llmgw/corp-ca.pem         # the domain's CA, when not in the system's
+    bind_dn: CN=svc-llmgw,OU=Service,DC=corp,DC=example
+    bind_password_file: /etc/llmgw/secrets/ldap-bind   # root-only
+    base_dn: OU=Staff,DC=corp,DC=example    # where people are
+    user_filter: (memberOf:1.2.840.113556.1.4.1941:=CN=llmgw-users,OU=Groups,DC=corp,DC=example)
+    label: Acme                             # "Sign in with your Acme account"
+    create_accounts: true
+    roles:                                  # by group CN or full DN; nested groups count
+      admin: [llmgw-admins]
+      operator: [llmgw-ops]
+    memberships:
+      ml-engineers: "team:Acme/ml"
+    sync_interval: 15m                      # negative turns the sync off
+```
+
+- **Service account:** an ordinary domain user is enough: it only reads.
+  It finds the person and reads their groups. The person's password is
+  checked by binding as them, and is never stored.
+- **Encryption:** `ldaps://`, or `ldap://` with `start_tls: true`.
+  Plaintext LDAP is refused, since passwords would cross the network.
+- **Certificate:** the domain controller's certificate must name it in
+  its subject alternative names: a name in the CN only is refused, as are
+  certificates with a negative serial number. Samba's own autogenerated
+  certificate is both, so a Samba DC needs one from a CA (`tls certfile`
+  in smb.conf). A CA file a control plane cannot read turns directory
+  sign-in off on that control plane, said in its log. Local accounts still
+  sign in.
+- **Who may sign in:** enabled user objects under `base_dn` that match
+  `user_filter`. The example admits members of `llmgw-users`, nested groups
+  included.
+- **Accounts:** an account is tied to the person's `objectGUID`, so a changed
+  mail or name is still the same account. An account that already exists
+  with the person's mail is taken over. Without `create_accounts`, only
+  people who already have an account can sign in. Local accounts, such as
+  the administrator `server init` made, keep signing in with their own
+  password.
+- **Sync:** every `sync_interval` the leader reads the directory.
+  - Someone disabled or deleted in AD is suspended and their sessions
+    end.
+  - When they are enabled again they are reinstated. An account an
+    administrator suspended by hand stays suspended.
+  - Roles follow groups, and memberships the directory gave are taken away
+    when the person leaves the group.
+  - A sync that would suspend more than half of the directory's accounts is
+    refused and logged, rather than locking everyone out over a wrong
+    `base_dn` or filter.
+- **Passwords:** a person's password is changed in AD. The gateway sends no
+  reset link for these accounts.
+
 ## Secrets in Vault
 
 Every setting that names a file holding a secret — the store's `@address`,
@@ -3088,6 +3573,8 @@ requests. On a slow model, set `timeouts.generation` higher.
 
 - `docs/choosing-models.md` — which models to run and how many, if the answer
   to "we have GPUs, now what" is not already obvious
+- `docs/large-models.md` — a model on several cards or several nodes: how it
+  is split, what each way needs of a card, and bringing one up on a fabric
 - `docs/data.md` — what is stored and what leaves the machine, for the review
   that happens before this is allowed near anyone's documents
 - `docs/reference.md` — every configuration key, generated from the source, so

docs/knowledge.md

@@ -3,9 +3,9 @@
 A knowledge base is a collection of a company's documents that the cluster
 can answer from. People put their documents into it from their own machines
 with `llmgw-kb`. The tool reads the files on that machine, cuts them into
-passages ("chunks"), has the gateway embed each passage with the person's own
-key, and sends the text and the vectors. The files themselves never leave
-the machine.
+passages ("chunks") and sends their text; the gateway embeds each passage
+with the person's own key and keeps the text and the vectors. The files
+themselves never leave the machine.
 
 ## Why retrieval, and not training
 
@@ -159,10 +159,12 @@ llmgw ctl config set router.admission.bands '[{name: gold, priority: 300, satura
 llmgw keys create import --project Acme/docs --band bulk
 ```
 
-The people's questions then go first, and the import waits behind them. A
-request that waits as long as its band allows is answered 504 with
-`Retry-After`, and `llmgw-kb` sends it again rather than counting the
-passage as failed. It gives up after 15 minutes.
+The people's questions then go first, and the import waits behind them. The
+gateway embeds a document's passages 32 at a time, four batches at once,
+enough to fill an embedding replica's slots; a batch told to wait (`Retry-After`)
+waits up to five minutes before the document is answered the same, and
+`llmgw-kb` sends it again rather than counting it as failed. It gives up
+after 15 minutes.
 
 ## For everyone: `llmgw-kb`
 
@@ -225,6 +227,7 @@ not changed.
 | `--include`, `--exclude` | Glob patterns. `*.pdf` matches a file name; `reports/**/*.xlsx` matches a path. |
 | `--hidden` | Reads hidden files and folders too (left out by default). |
 | `-v` | Lists unchanged files too. |
+| `--embed-here` | Embeds the passages from this machine and sends the vectors. With a gateway that does not embed them itself it does so anyway. |
 
 Documents are named by their path under the folder, with forward slashes,
 on every system. With several folders, each folder's own name comes first.
@@ -259,13 +262,12 @@ scanned page with no OCR.
 
 ### What leaves your machine
 
-For each new or changed document, two things leave the machine, both over
-the gateway's TLS connection:
-
-- **The passages, to be embedded.** They go through `/v1/embeddings` like
-  any request of yours. Your key's limits, budget and guardrails apply.
-- **The document itself.** Its name, its file's SHA-256 digest and size,
-  and the passages with their vectors.
+For each new or changed document, one request leaves the machine, over the
+gateway's TLS connection: its name, its file's SHA-256 digest and size, and
+its passages' text. The gateway embeds the passages through `/v1/embeddings`
+as you, so your key's limits, budget and guardrails apply as if you had
+asked. That is about a kilobyte a passage; embedding here (`--embed-here`)
+brings each vector down and sends it up again, some thirty times more.
 
 The file itself is never sent. `--dry-run` shows exactly what would be.
 

docs/kong.md

@@ -0,0 +1,95 @@
+# llmgw and Kong
+
+For a site that already runs Kong. The two meet over plain HTTP: Kong in
+front of llmgw, as one more API it governs, or Kong behind llmgw, as an
+OpenAI-compatible provider. Nothing of either is built into the other.
+
+Tried with Kong Gateway 3.9 (`kong:3.9`, the last open-source release; 3.10
+and later need a Kong licence) in DB-less mode, in front of llmgw.
+
+## Kong in front of llmgw
+
+Two ways, both tried.
+
+**A plain route.** Kong forwards the request as it came. Tried with chat
+completions, streamed and not; llmgw's other APIs — Anthropic's
+`/v1/messages`, `/v1/responses`, embeddings, pictures — go the same way,
+since Kong does not read them. Kong adds its own authentication, rate limits
+and logging; llmgw still checks the key, the budget and the guardrails.
+
+```yaml
+_format_version: "3.0"
+services:
+- name: llmgw
+  url: https://llm.example.com          # llmgw's client port
+  routes:
+  - name: llmgw
+    paths: [/llmgw]                      # /llmgw/v1/chat/completions → /v1/chat/completions
+```
+
+**Kong's `ai-proxy` plugin**, for Kong's own token statistics on a chat
+route. llmgw is an OpenAI provider whose `upstream_url` is llmgw:
+
+```yaml
+services:
+- name: llmgw-chat
+  url: https://llm.example.com
+  routes:
+  - name: chat
+    paths: [/chat]
+  plugins:
+  - name: ai-proxy
+    config:
+      route_type: llm/v1/chat
+      logging: {log_statistics: true, log_payloads: false}
+      model:
+        provider: openai
+        name: qwen-coder                 # a model llmgw serves
+        options:
+          upstream_url: https://llm.example.com/v1/chat/completions
+```
+
+**Keys.** Without an `auth` block, `ai-proxy` passes the client's
+`Authorization` header on: each team keeps its own llmgw key, and llmgw's
+budgets, limits, guardrails and usage stay per team. With
+`auth: {header_name: Authorization, header_value: "Bearer sk-llmgw-…"}` Kong
+sends one key of its own instead, and llmgw sees every caller as that key —
+then budgets per team are Kong's to keep.
+
+**What Kong counts.** For a whole answer Kong reads llmgw's `usage` and
+records prompt and completion tokens as llmgw did. For a streamed answer
+Kong 3.9 records an estimate of the prompt tokens and no completion tokens,
+even with `stream_options.include_usage` set — the usage chunk reaches it
+and is not read. llmgw's own accounting counts both; use its usage export
+(`llmgw ctl usage export`) or `/admin/usage` for figures to bill by.
+
+**Timeouts.** A long answer from a model still loading outlasts Kong's
+60-second defaults: set the service's `read_timeout` to the time a model may
+take to start, as for nginx in [install.md](install.md).
+
+## Kong behind llmgw
+
+Not tried here. Kong's AI routes speak OpenAI's API, so llmgw reaches models Kong fronts as
+it reaches any provider: a model whose source is `external`.
+
+```yaml
+- name: kong-gpt
+  source: external
+  external:
+    url: https://kong.example.com/openai     # Kong's route, without /v1
+    model: gpt-4o-mini
+    api_key_file: /etc/llmgw/secrets/kong-consumer.key
+```
+
+The key is the one Kong's own authentication asks of a consumer. As a
+fallback (`fallbacks: [kong-gpt]`) it is used only when the cluster has no
+room.
+
+## Which to choose
+
+Kong in front when the site's API policy says every API goes through Kong:
+llmgw is then one more upstream, and its per-team accounting still holds
+when each team keeps its own key. Kong behind when the site already reaches
+outside providers through Kong and llmgw should too. llmgw does not need
+Kong for anything it does itself — keys, budgets, guardrails, routing to
+its own replicas.

docs/large-models.md

@@ -0,0 +1,145 @@
+# Large models: several cards, several nodes
+
+A model too big for one card runs on several. llmgw chooses how from the
+model's own figures and the cluster as it is; this page is the rules it
+follows, the commands, and what to look at when a first one is brought up
+on new hardware.
+
+## How a model is split
+
+In order, the first that fits:
+
+1. **One card.** Nothing to split.
+2. **Several cards of one node, tensor parallel.** Every layer is cut
+   across the cards, so they talk for every token: they must be on one
+   NVLink domain. The agent reads `nvidia-smi topo -m` and gives a replica
+   the cards with the most NVLink between them
+   ([install.md](install.md#nvlink-if-your-gpus-have-it)).
+3. **Several nodes, pipeline parallel between them.** Each node holds a
+   run of layers on all its cards (tensor parallel inside it), and only a
+   layer's output crosses to the next node. The nodes must share one
+   InfiniBand or RoCE fabric: a replica never spans two, and never a node
+   with none. Any number of nodes, not only two or four.
+
+The plan takes the fewest cards, then the fewest nodes, then the better
+precision up to eight bits.
+
+**Tensor width and the KV heads.** The cards split the model's KV heads
+among them, or past their number each card holds a copy of one. So the
+width divides the KV heads or is a multiple of them: a model with 8 KV
+heads runs 2, 4, 8 or 16 wide, not 12. Qwen3-235B has 4 and runs on 8.
+
+**Mixture of experts.** A model of experts (Qwen3-235B-A22B, DeepSeek-V3,
+Llama 4, Mixtral) on more than one card is served with vLLM's
+`--enable-expert-parallel`: each card holds whole experts rather than a
+slice of every one, which is less traffic per token. It is read from
+`config.json` (`num_experts`, `n_routed_experts`, `num_local_experts`).
+
+**When it does not fit.** A smaller precision first: an FP8 or AWQ
+repository of the same model, or a GGUF quantisation on llama.cpp if one
+node's cards hold it. Then more nodes. `llmgw ctl model plan REPO
+--precision bf16,fp8` shows each precision's fit from the model's config.
+
+## What a way needs
+
+Each way the plan offers says what a replica needs of each card, part by
+part, and of all its cards together:
+
+```
+$ llmgw ctl model plan meta-llama/Llama-3.3-70B-Instruct --format safetensors --context 32768
+FILE      SIZE    BEST WAY        A CARD   OF     ALL CARDS  NOW
+original  131 GB  4 × h100-80g    37.4 GB  72 GB  150 GB     free
+
+Best: original on 4 × h100-80g: 37.4 GB a card (weights 32.9 + context 2.5 + engine 2.0) of 72 usable; 150 GB on 4 cards.
+The context costs 0.31 GB per 1000 tokens, the whole model (--context to plan another).
+```
+
+- **weights:** the files, divided over the cards.
+- **context:** the KV cache for the context planned, divided likewise.
+- **engine:** the engine's own: 2 GB and a fiftieth of the weights for vLLM.
+- **usable:** 90% of a card; the rest is the driver's and fragmentation's.
+
+The console's **Serve a model** shows the same for every way a file runs.
+A context longer than planned is checked against it before anything is
+fetched.
+
+## Serving one
+
+Without flags the plan's best way is taken:
+
+```
+llmgw ctl model serve Qwen/Qwen3-235B-A22B-Instruct-2507-FP8 --format safetensors --context-length 32768
+```
+
+Or a way given by hand, for instance two nodes of eight:
+
+```
+llmgw ctl model serve meta-llama/Llama-3.3-70B-Instruct --format safetensors \
+    --gpu-class h100-80g --gpus 8 --nodes 2 --env NCCL_DEBUG=INFO
+```
+
+`--gpus` is the cards on each node and `--nodes` the nodes. The pipeline
+is the nodes and the tensor width the cards of each.
+
+`--env KEY=VALUE` goes into the engine's environment on every node:
+`NCCL_DEBUG=INFO` while bringing a cluster up, `NCCL_IB_*` to steer it.
+Only the variables engines are tuned with are taken. llmgw already sets
+these:
+- `NCCL_IB_HCA` to the fabric's adapters;
+- `NCCL_IB_GID_INDEX` on RoCE;
+- `NCCL_SOCKET_IFNAME` to the management network;
+- for an NVLink domain spanning nodes, `NCCL_MNNVL_ENABLE`.
+
+The job's first step says what it needs of each card. The weights then
+come to the mirror once and from it to each node. The startup timeout (20
+minutes unless the profile's `startup_timeout` says otherwise) runs from
+when a node's download last moved. So a model of hundreds of gigabytes is
+not failed while it is still arriving, and one whose download stops is
+failed that long after.
+
+## Watching it come up
+
+| What | Where |
+|---|---|
+| The replica and its shards, one per node, each with its download | `llmgw ctl replicas` |
+| Why it is not placed | `llmgw ctl explain-placement MODEL` |
+| A node's engine output (NCCL's lines with `NCCL_DEBUG=INFO`) | `llmgw ctl logs NODE --source SHARD` |
+| The bandwidth between two nodes, rail by rail | `llmgw ctl fabric-test NODE NODE` |
+| Each node's GPUs, NVLink and adapters | `llmgw doctor` on the node; its page under /admin |
+| Every step of a start, across nodes | the `replica start` trace ([install.md](install.md)) |
+
+With `NCCL_DEBUG=INFO`, NCCL says which transport it took between nodes:
+`NET/IB` is the fabric. `NET/Socket` means it fell back to TCP, and the
+model will run, slowly.
+
+## Bringing it up on new hardware
+
+A first run on a fabric, in order. Each step is worth its output if
+something goes wrong.
+
+1. **The nodes.** Add each with its fabric:
+   `llmgw node add host --fabric ib-a:mlx5_0,mlx5_1`. Then
+   `llmgw ctl nodes` shows every node ready, on `ib-a`.
+2. **The fabric.** `llmgw ctl fabric-test node1 node2`: each rail at its
+   rated speed (a 400 Gb/s rail near 45 GB/s).
+3. **One node, several cards.** A dense 70B at bf16 on four or eight
+   cards of one node, by the plan:
+   `llmgw ctl model serve meta-llama/Llama-3.3-70B-Instruct --format safetensors`.
+   Ready, then a question answered.
+4. **Two nodes.** The same model forced over two:
+   `--gpu-class CLASS --gpus 8 --nodes 2 --env NCCL_DEBUG=INFO`, under
+   another `--name`. Ready, answering, and `NET/IB` in both shards' logs.
+5. **Experts.** A mixture-of-experts model on one node's eight cards,
+   for instance `Qwen/Qwen3-235B-A22B-Instruct-2507-FP8`: its profile
+   carries `--enable-expert-parallel` (`llmgw ctl models`, or its
+   definition from the admin API).
+6. **A node lost.** With the two-node replica serving, stop one node's
+   agent (`systemctl stop llmgw-agent`): the replica fails and is placed
+   again once the node is back or another has room. Nothing is left
+   holding cards.
+
+For each, worth keeping:
+- the time from serve to ready;
+- tokens a second from `llmgw ctl bench`;
+- the plan's per-card figure against what `nvidia-smi` shows once loaded;
+- anything it said that was wrong.

docs/onboarding.md

@@ -54,10 +54,20 @@ on the page that creates it and never again.
 
 ### Connecting an editor
 
-The account page's **Connect your editor** makes a key for Continue, Codex or
-Cline and shows what the tool needs with that key, this gateway's address and a
-model already in it:
+The account page's **Connect your editor** makes a key for VS Code, Continue,
+Codex or Cline and shows what the tool needs with that key, this gateway's
+address and a model already in it:
 
+- **VS Code** — llmgw's own extension, downloaded from the gateway at
+  `/setup/vscode/llmgw.vsix` with this gateway's address already in it. It
+  offers every chat model the key may use to VS Code itself: the chat's model
+  picker, agent mode, and any extension that asks VS Code for a language model
+  (Cline's "VS Code LM API" provider among them), with no setup of their own.
+  **llmgw: Sign In** in VS Code opens this page with VS Code chosen; the page's
+  **Open in VS Code** link hands the key back, and the extension keeps it in
+  VS Code's secret storage. A link the extension did not ask for is confirmed
+  first, with the gateway's address shown, since it decides where code is sent.
+  **llmgw: Enter API Key** takes a pasted one instead.
 - **Continue** — an assistant file of its own, `~/.continue/assistants/llmgw.yaml`,
   so their `config.yaml` is not touched.
 - **Codex** — a provider and a profile in `~/.codex/config.toml`, run with

docs/quick-install.md

@@ -8,7 +8,7 @@ explains every choice.
 
 | | |
 |---|---|
-| **A control plane** | One machine, or three for high availability (the store replicated, either one able to take over). Linux, x86-64 or ARM64: Debian 12, Ubuntu 22.04+ or RHEL 10. No GPU needed; 2 GB RAM, 20 GB disk each — 8 GB RAM when it is also a node running the starter model and the two judges. |
+| **A control plane** | One machine, or three for high availability (the store replicated, either one able to take over). Linux, x86-64 or ARM64: Debian 12, Ubuntu 22.04+ or RHEL 10. No GPU needed; 2 GB RAM, 20 GB disk each — 12 GB RAM when it is also a node running the starter model and the two judges, which setup checks before it installs anything; four cores or more, or the judges on machines of their own, keep a judgment within its wait. |
 | **GPU nodes** (optional to start) | The same Linux, with the NVIDIA driver installed. vLLM needs driver 525 or newer and a Turing GPU or newer; a V100 gets an older vLLM. |
 | **root** | on the control plane. On the other two of a three-machine setup, `sudo` (its password is asked for if it needs one); on nodes, `sudo` without a password. |
 | **SSH** | from the control plane to the other machines. The setup screens take a key, the ssh agent or a password; `node add` uses ssh keys. A machine nothing may log into joins with a code instead (`llmgw join`). |
@@ -146,7 +146,35 @@ agent is stopped.
 ## 4. Add a model
 
 Open `/admin/mirror` and choose **Explore models**. It lists what is popular on
-Hugging Face, showing only what your nodes can run.
+Hugging Face, showing only what your nodes can run: judged by the cluster as it
+is now — the largest card and its compute capability, the most memory on one
+node — so a model too big for them, in a form those cards lack (FP8 needs 8.9),
+or in neither GGUF nor safetensors is left out, and the page says how many.
+Without GPUs it lists GGUF only. Untick **only what these nodes can run** to
+see everything. On a model's page a file too big for the cluster is shown
+without a **Fetch** button, with what it would need.
+
+The **CPU tok/s** column is about how fast one reply would come on the CPU of
+the fastest node whose memory holds the model at Q4_K_M; a model's page gives
+it for each GGUF file by its own size. Every node's agent measures how fast its
+memory reads when it starts (it is in the agent's log as `memory_gbs`), and a
+token on a CPU reads every weight once: the estimate is that speed over the
+model's size — for a model of experts named like `30B-A3B`, its active part.
+On the test cluster it came within 15% of what llama.cpp measured. Several
+replies at once share the reads and each is slower.
+
+**GPU tok/s** is the same on the cards, for the layout this cluster would
+give the model — the fewest cards that hold it, of each class, the fastest of
+those; its tooltip says which ("2× h100-80g, NVLink, vLLM", "2 nodes × 1×
+a100-80g over ib0 (InfiniBand 200 Gb/s), vLLM"). A card's memory bandwidth is
+known from its model name (an H100 SXM and an H100 PCIe differ by half); a card
+not in the table gets no figure. Tensor parallel across a node's cards divides
+what each reads, and adds two all-reduces a layer, short over NVLink and
+longer over PCIe; llama.cpp across cards splits by layer, so the cards take
+turns and a reply is no faster than on one; a pipeline across nodes takes turns
+too, and adds a hop over the fabric for each node. One card's figures were
+measured on the test cluster's RTX 6000; tensor parallel and the fabric are
+from what NCCL is known to take, not measured here.
 
 1. Click a model to read its card.
 2. Pick one of its files, usually a `q4_k_m` for a first try, and click

docs/reference.md

@@ -37,6 +37,7 @@ rather than repeated.
 | `default_tpm` | `int` | [Auth](#auth) |
 | `signup_open` | `bool` | [Auth](#auth) |
 | `oidc` | `OIDC` | [Auth](#auth) |
+| `ldap` | `LDAP` | [Auth](#auth) |
 | `scim` | `SCIM` | [Auth](#auth) |
 | `max_key_ttl` | `time.Duration` | [Auth](#auth) |
 | `personal` | `Personal` | [Auth](#auth) |
@@ -52,6 +53,7 @@ rather than repeated.
 | `retain_days` | `int` | [Batch](#batch) |
 | `max_bytes` | `int64` | [Cache](#cache) |
 | `max_entry_bytes` | `int64` | [Cache](#cache) |
+| `embedding_model` | `string` | [Cache](#cache) |
 | `model` | `string` | [Canary](#canary) |
 | `percent` | `int` | [Canary](#canary) |
 | `min_requests` | `int` | [Canary](#canary) |
@@ -105,10 +107,13 @@ rather than repeated.
 | `url` | `string` | [External](#external) |
 | `model` | `string` | [External](#external) |
 | `api_key_file` | `string` | [External](#external) |
+| `api_key_files` | `[]ExternalKey` | [External](#external) |
 | `peer` | `string` | [External](#external) |
 | `api` | `string` | [External](#external) |
 | `workflow` | `string` | [External](#external) |
 | `output` | `string` | [External](#external) |
+| `file` | `string` | [ExternalKey](#externalkey) |
+| `weight` | `float64` | [ExternalKey](#externalkey) |
 | `budgets` | `[]FacilityBudget` | [Facility](#facility) |
 | `margin` | `float64` | [Facility](#facility) |
 | `gpu_watts` | `float64` | [Facility](#facility) |
@@ -144,6 +149,21 @@ rather than repeated.
 | `tokenize_timeout` | `time.Duration` | [KVIndex](#kvindex) |
 | `min_blocks` | `int` | [KVIndex](#kvindex) |
 | `max_blocks` | `int` | [KVIndex](#kvindex) |
+| `urls` | `[]string` | [LDAP](#ldap) |
+| `start_tls` | `bool` | [LDAP](#ldap) |
+| `ca_file` | `string` | [LDAP](#ldap) |
+| `ca` | `string` | [LDAP](#ldap) |
+| `bind_dn` | `string` | [LDAP](#ldap) |
+| `bind_password_file` | `string` | [LDAP](#ldap) |
+| `base_dn` | `string` | [LDAP](#ldap) |
+| `group_base_dn` | `string` | [LDAP](#ldap) |
+| `user_filter` | `string` | [LDAP](#ldap) |
+| `label` | `string` | [LDAP](#ldap) |
+| `create_accounts` | `bool` | [LDAP](#ldap) |
+| `roles` | `map[string][]string` | [LDAP](#ldap) |
+| `memberships` | `map[string]string` | [LDAP](#ldap) |
+| `sync_interval` | `time.Duration` | [LDAP](#ldap) |
+| `timeout` | `time.Duration` | [LDAP](#ldap) |
 | `contact` | `string` | [Landing](#landing) |
 | `notice` | `string` | [Landing](#landing) |
 | `language` | `string` | [Landing](#landing) |
@@ -160,6 +180,7 @@ rather than repeated.
 | `parallel` | `int` | [LlamaCppConfig](#llamacppconfig) |
 | `threads` | `int` | [LlamaCppConfig](#llamacppconfig) |
 | `api` | `string` | [Mirror](#mirror) |
+| `peers` | `[]string` | [Mirror](#mirror) |
 | `tls` | `tlsconf.Config` | [Mirror](#mirror) |
 | `registry` | `string` | [Mirror](#mirror) |
 | `timeout` | `time.Duration` | [Mirror](#mirror) |
@@ -168,8 +189,10 @@ rather than repeated.
 | `aliases` | `[]string` | [Model](#model) |
 | `description` | `string` | [Model](#model) |
 | `source` | `string` | [Model](#model) |
+| `allow_pickle` | `bool` | [Model](#model) |
 | `profiles` | `[]Profile` | [Model](#model) |
 | `scaling` | `Scaling` | [Model](#model) |
+| `stopped` | `*Scaling` | [Model](#model) |
 | `class` | `string` | [Model](#model) |
 | `owner` | `string` | [Model](#model) |
 | `external` | `*External` | [Model](#model) |
@@ -238,6 +261,7 @@ rather than repeated.
 | `require_capabilities` | `bool` | [Policy](#policy) |
 | `validate_structured` | `bool` | [Policy](#policy) |
 | `judge` | `*JudgePolicy` | [Policy](#policy) |
+| `services` | `[]Service` | [Policy](#policy) |
 | `stream` | `string` | [Policy](#policy) |
 | `enabled` | `bool` | [Prefix](#prefix) |
 | `max_nodes` | `int` | [Prefix](#prefix) |
@@ -301,6 +325,7 @@ rather than repeated.
 | `injection` | `string` | [Rules](#rules) |
 | `deny` | `[]Pattern` | [Rules](#rules) |
 | `max_chars` | `int` | [Rules](#rules) |
+| `restore` | `bool` | [Rules](#rules) |
 | `token_file` | `string` | [SCIM](#scim) |
 | `python` | `string` | [SGLangConfig](#sglangconfig) |
 | `ttft_p99` | `time.Duration` | [SLO](#slo) |
@@ -361,8 +386,20 @@ rather than repeated.
 | `facility` | `Facility` | [Server](#server) |
 | `federation` | `Federation` | [Server](#server) |
 | `endpoints` | `[]Endpoint` | [Server](#server) |
+| `name` | `string` | [Service](#service) |
+| `url` | `string` | [Service](#service) |
+| `header_files` | `map[string]string` | [Service](#service) |
+| `body` | `string` | [Service](#service) |
+| `blocked` | `string` | [Service](#service) |
+| `reason` | `string` | [Service](#service) |
+| `on` | `string` | [Service](#service) |
+| `action` | `string` | [Service](#service) |
+| `timeout` | `time.Duration` | [Service](#service) |
 | `stopped` | `bool` | [ServingSettings](#servingsettings) |
 | `bin` | `string` | [SimConfig](#simconfig) |
+| `dir` | `string` | [StrataConfig](#strataconfig) |
+| `python` | `string` | [StrataConfig](#strataconfig) |
+| `engine` | `string` | [StrataConfig](#strataconfig) |
 | `python` | `string` | [TRTLLMConfig](#trtllmconfig) |
 | `store` | `string` | [Threads](#threads) |
 | `retain_hours` | `int` | [Threads](#threads) |
@@ -394,6 +431,7 @@ rather than repeated.
 | `secret_file` | `string` | [Webhook](#webhook) |
 | `prompt_per_1k` | `int64` | [accounting.Price](#accountingprice) |
 | `completion_per_1k` | `int64` | [accounting.Price](#accountingprice) |
+| `cached_per_1k` | `int64` | [accounting.Price](#accountingprice) |
 | `per_image` | `int64` | [accounting.Price](#accountingprice) |
 | `per_mesh` | `int64` | [accounting.Price](#accountingprice) |
 | `name` | `string` | [admission.Band](#admissionband) |
@@ -432,6 +470,7 @@ rather than repeated.
 | `queue_ttl` | `time.Duration` | [config.Band](#configband) |
 | `prompt_per_1k` | `int64` | [config.Price](#configprice) |
 | `completion_per_1k` | `int64` | [config.Price](#configprice) |
+| `cached_per_1k` | `int64` | [config.Price](#configprice) |
 | `per_image` | `int64` | [config.Price](#configprice) |
 | `per_mesh` | `int64` | [config.Price](#configprice) |
 | `disabled` | `[]string` | [engines.Config](#enginesconfig) |
@@ -441,6 +480,7 @@ rather than repeated.
 | `trtllm` | `TRTLLMConfig` | [engines.Config](#enginesconfig) |
 | `sim` | `SimConfig` | [engines.Config](#enginesconfig) |
 | `comfyui` | `ComfyUIConfig` | [engines.Config](#enginesconfig) |
+| `strata` | `StrataConfig` | [engines.Config](#enginesconfig) |
 | `enabled` | `*bool` | [guard.Config](#guardconfig) |
 | `default` | `[]string` | [guard.Config](#guardconfig) |
 | `policies` | `map[string]Policy` | [guard.Config](#guardconfig) |
@@ -616,6 +656,15 @@ OIDC is sign-in through an identity provider.
 
 Takes a [OIDC](#oidc) block.
 
+### `ldap`
+
+`LDAP`
+
+LDAP is sign-in against a directory, Active Directory above all, and
+the accounts kept in step with it.
+
+Takes a [LDAP](#ldap) block.
+
 ### `scim`
 
 `SCIM`
@@ -728,6 +777,15 @@ Past it, the answers used longest ago go first.
 MaxEntryBytes bounds one answer; a longer one is not kept. 1 MB
 unless set.
 
+### `embedding_model`
+
+`string`
+
+EmbeddingModel embeds the questions of projects that reuse answers to
+similar ones (llmgw keys cache --similar): an embedding model in the
+catalog. Unset, those projects reuse only the same request's answer.
+The gateway asks it on its own account, as it asks a judge.
+
 ## Canary
 
 ### `model`
@@ -1103,6 +1161,15 @@ APIKeyFile holds the provider's key, on the control plane. A file
 rather than the key itself, so the key is in neither the catalog, the
 store nor the audit log; empty for a provider that asks for none.
 
+### `api_key_files`
+
+`[]ExternalKey`
+
+APIKeyFiles are several keys for the provider, in place of
+APIKeyFile: one endpoint each (external:MODEL#1, #2…), so a key that
+answers 429 or 401 is passed over while its breaker is open and the
+request goes to another. A provider's limits are per key.
+
 ### `peer`
 
 `string`
@@ -1135,6 +1202,20 @@ plane.
 
 Output is what it makes: pictures, or meshes (see ComfyUI.Output).
 
+## ExternalKey
+
+### `file`
+
+`string`
+
+File holds the key, on the control plane, as APIKeyFile does.
+
+### `weight`
+
+`float64`
+
+Weight is its share of the requests against the others'; zero is 1.
+
 ## Facility
 
 ### `budgets`
@@ -1401,6 +1482,114 @@ MaxBlocks bounds how many of a prompt's blocks are hashed and looked
 up. Beyond it a longer match still helps, but the difference no longer
 decides anything. Zero takes 4096.
 
+## LDAP
+
+### `urls`
+
+`[]string`
+
+URLs are the directory's servers, tried in turn: ldaps:// (636), or
+ldap:// (389) with StartTLS.
+
+### `start_tls`
+
+`bool`
+
+StartTLS upgrades an ldap:// connection before anything is sent. A
+password never crosses a connection without TLS: ldap:// without it
+is refused.
+
+### `ca_file`
+
+`string`
+
+CAFile is the authority the servers' certificates are checked against,
+when it is not the system's: an AD Certificate Services root.
+
+### `ca`
+
+`string`
+
+CA is the same authority written out, PEM: kept in the cluster's
+settings, so no file has to be put on every control plane. Used in
+place of CAFile when both are set.
+
+### `bind_dn`
+
+`string`
+
+BindDN and the file holding its password: a service account that may
+read users and groups. Nothing is written to the directory.
+
+### `bind_password_file`
+
+`string`
+
+### `base_dn`
+
+`string`
+
+BaseDN is where people are searched for, subtree included.
+
+### `group_base_dn`
+
+`string`
+
+GroupBaseDN is where their groups are; empty is BaseDN's domain root.
+
+### `user_filter`
+
+`string`
+
+UserFilter narrows who may sign in, ANDed with the login match: a
+group (memberOf=...) or an OU's people only. Empty is every enabled
+user object.
+
+### `label`
+
+`string`
+
+Label is what the form says to sign in with: "Sign in with your
+<label> account". Empty is "Active Directory".
+
+### `create_accounts`
+
+`bool`
+
+CreateAccounts makes an account, active, for a person the directory
+vouches for and the gateway does not know. Off, only existing accounts
+sign in this way.
+
+### `roles`
+
+`map[string][]string`
+
+Roles maps a staff role (viewer, operator, billing, admin) to the
+groups that give it, by name (CN) or whole DN. Set at every sign-in
+and sync: someone taken out of the group loses the role.
+
+### `memberships`
+
+`map[string]string`
+
+Memberships maps a group, by CN or DN, to a place in the tree —
+org:NAME, team:ORG/TEAM, project:ORG/TEAM/PROJECT — joined at sign-in
+and kept by the sync, which also takes away a place whose group the
+person has left.
+
+### `sync_interval`
+
+`time.Duration`
+
+SyncInterval is how often the leader reads the directory. Zero is
+15m; negative turns the sync off, leaving only sign-in.
+
+### `timeout`
+
+`time.Duration`
+
+Timeout bounds each round trip to a server. Zero is 10s.
+
 ## Landing
 
 ### `contact`
@@ -1539,6 +1728,14 @@ The management port, not the one nodes fetch bytes from. Those are two
 listeners on the mirror precisely so this one can be locked down without
 re-certifying every agent's fetcher.
 
+### `peers`
+
+`[]string`
+
+Peers are the management addresses of mirrors kept in step with this
+one (llmgw mirror serve --peer): asked when it cannot be reached, and
+a node given the same file on one of them while it is down.
+
 ### `tls`
 
 `tlsconf.Config`
@@ -1608,6 +1805,16 @@ choice by guesswork.
 
 Source is the weights path or a HuggingFace id.
 
+### `allow_pickle`
+
+`bool`
+
+AllowPickle lets the nodes fetch this model's weights, or its
+adapters', in a pickle format (.bin, .pt, .pth, .ckpt), which run code
+as they are loaded. Off, such a source is refused when the model is
+added and by the node before it fetches anything. For a model that has
+no safetensors or GGUF form and whose files were checked.
+
 ### `profiles`
 
 `[]Profile`
@@ -1618,6 +1825,16 @@ Source is the weights path or a HuggingFace id.
 
 Takes a [Scaling](#scaling) block.
 
+### `stopped`
+
+`*Scaling`
+
+Stopped is the scaling a model had when an administrator stopped it:
+kept in the catalog with none running (Scaling 0/0) until started
+again with this. Nil for a model not stopped.
+
+Takes a [Scaling](#scaling) block.
+
 ### `class`
 
 `string`
@@ -2136,6 +2353,12 @@ Judge has a judge model on the cluster read the text too.
 
 Takes a [JudgePolicy](#judgepolicy) block.
 
+### `services`
+
+`[]Service`
+
+Services are outside guardrails asked over HTTP, beside the judge.
+
 ### `stream`
 
 `string`
@@ -2610,6 +2833,14 @@ Deny are patterns, matched against the text as a model reads it.
 
 MaxChars refuses text longer than this; zero is no limit.
 
+### `restore`
+
+`bool`
+
+Restore, on input, puts what redact rewrote as placeholders back into
+the answer: the model reads "[EMAIL_1]", the client reads its own
+address. Only the values that request sent, only into its answer.
+
 ## SCIM
 
 ### `token_file`
@@ -3117,6 +3348,67 @@ Endpoints is the phase-1 static replica list. It is only consulted when
 no model declares a profile, which is what makes a router-only smoke test
 against sim-engines possible without a control plane.
 
+## Service
+
+### `name`
+
+`string`
+
+Name says which service decided, in the verdict's rule.
+
+### `url`
+
+`string`
+
+URL is POSTed the body.
+
+### `header_files`
+
+`map[string]string`
+
+HeaderFiles are headers whose values are read from files each time,
+so a rotated key needs no restart: {Authorization: /etc/…/lakera}.
+
+### `body`
+
+`string`
+
+Body is the request, a template given .Text; {{json .Text}} writes it
+as a JSON string. Empty is {"input": <text>}.
+
+### `blocked`
+
+`string`
+
+Blocked is where in the answer the service says the text is unsafe:
+a dotted path, numbers for list items (results.0.flagged). True, a
+number above zero, a non-empty list or string other than "false" is
+unsafe.
+
+### `reason`
+
+`string`
+
+Reason is where it says why, for the verdict; optional.
+
+### `on`
+
+`string`
+
+On: input, output or both. Empty is input.
+
+### `action`
+
+`string`
+
+Action on unsafe: block or flag. Empty is block.
+
+### `timeout`
+
+`time.Duration`
+
+Timeout bounds one call. Empty is 3s; past it the policy's fail says.
+
 ## ServingSettings
 
 ### `stopped`
@@ -3138,6 +3430,27 @@ entries ask. In force on every control plane within seconds.
 Bin is the llmgw binary itself; the engine is one of its subcommands.
 Empty means whatever started this agent, which is right almost always.
 
+## StrataConfig
+
+### `dir`
+
+`string`
+
+Dir is Strata's source directory, where setup.py and serve/ are.
+
+### `python`
+
+`string`
+
+Python is the interpreter of its environment; Dir's .venv when unset.
+
+### `engine`
+
+`string`
+
+Engine is the directory of its prebuilt engine, where the strata
+binary and the CUDA libraries it ships are; Dir's engine/ when unset.
+
 ## TRTLLMConfig
 
 ### `python`
@@ -3355,6 +3668,15 @@ is sha256=<hex HMAC of the body>.
 
 `int64`
 
+### `cached_per_1k`
+
+`int64`
+
+CachedPer1k is what a prompt token costs that the engine or provider
+read from its cache instead of computing: the part of prompt_tokens
+the answer counts as cached_tokens. Zero charges those at
+PromptPer1k, as before there was a rate for them.
+
 ### `per_image`
 
 `int64`
@@ -3629,6 +3951,14 @@ had rather wait behind people than be turned away.
 
 `int64`
 
+### `cached_per_1k`
+
+`int64`
+
+CachedPer1k is the cost of a prompt token the engine or provider read
+from its cache (the answer's cached_tokens, counted within the
+prompt's). Zero charges them at prompt_per_1k.
+
 ### `per_image`
 
 `int64`
@@ -3693,6 +4023,15 @@ ComfyUI makes pictures; offered by a node whose ComfyUI is named here.
 
 Takes a [ComfyUIConfig](#comfyuiconfig) block.
 
+### `strata`
+
+`StrataConfig`
+
+Strata serves a few mixture-of-experts models from RAM and one card;
+offered by a node whose Strata is named here, or that installed it.
+
+Takes a [StrataConfig](#strataconfig) block.
+
 ## guard.Config
 
 ### `enabled`

go.mod

@@ -12,6 +12,7 @@ require (
 	github.com/charmbracelet/x/ansi v0.11.6
 	github.com/coreos/go-oidc/v3 v3.21.0
 	github.com/go-jose/go-jose/v4 v4.1.4
+	github.com/go-ldap/ldap/v3 v3.4.15
 	github.com/go-zeromq/zmq4 v0.17.0
 	github.com/jackc/pgx/v5 v5.11.0
 	github.com/knadh/koanf/parsers/yaml v1.1.1
@@ -45,6 +46,7 @@ require (
 require (
 	filippo.io/edwards25519 v1.2.0 // indirect
 	filippo.io/hpke v0.4.0 // indirect
+	github.com/Azure/go-ntlmssp v0.1.1 // indirect
 	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
@@ -57,6 +59,7 @@ require (
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
+	github.com/go-asn1-ber/asn1-ber v1.5.8 // indirect
 	github.com/go-logr/logr v1.4.4 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect

go.sum

@@ -8,8 +8,12 @@ filippo.io/edwards25519 v1.2.0 h1:crnVqOiS4jqYleHd9vaKZ+HKtHfllngJIiOpNpoJsjo=
 filippo.io/edwards25519 v1.2.0/go.mod h1:xzAOLCNug/yB62zG1bQ8uziwrIqIuxhctzJT18Q77mc=
 filippo.io/hpke v0.4.0 h1:p575VVQ6ted4pL+it6M00V/f2qTZITO0zgmdKCkd5+A=
 filippo.io/hpke v0.4.0/go.mod h1:EmAN849/P3qdeK+PCMkDpDm83vRHM5cDipBJ8xbQLVY=
+github.com/Azure/go-ntlmssp v0.1.1 h1:l+FM/EEMb0U9QZE7mKNEDw5Mu3mFiaa2GKOoTSsNDPw=
+github.com/Azure/go-ntlmssp v0.1.1/go.mod h1:NYqdhxd/8aAct/s4qSYZEerdPuH1liG2/X9DiVTbhpk=
 github.com/NVIDIA/go-nvml v0.13.4-0 h1:o3jp9u2x1R9ShFE3v+Aesp55XOSIQFMJz/VGNUcJaNE=
 github.com/NVIDIA/go-nvml v0.13.4-0/go.mod h1:id63qwpoDWpFXwnwM6psDCSqW4BmNu6mWpr4YeQtPGo=
+github.com/alexbrainman/sspi v0.0.0-20250919150558-7d374ff0d59e h1:4dAU9FXIyQktpoUAgOJK3OTFc/xug0PCXYCqU0FgDKI=
+github.com/alexbrainman/sspi v0.0.0-20250919150558-7d374ff0d59e/go.mod h1:cEWa1LVoE5KvSD9ONXsZrj0z6KqySlCCNKHlLzbqAt4=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -46,8 +50,12 @@ github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6
 github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f/go.mod h1:vw97MGsxSvLiUE2X8qFplwetxpGLQrlU1Q9AUEIzCaM=
 github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
 github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
+github.com/go-asn1-ber/asn1-ber v1.5.8 h1:H9AZkK22UOmfX8J84ubyaZxKJZ3FMHVwn8swoMML7iQ=
+github.com/go-asn1-ber/asn1-ber v1.5.8/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
 github.com/go-jose/go-jose/v4 v4.1.4 h1:moDMcTHmvE6Groj34emNPLs/qtYXRVcd6S7NHbHz3kA=
 github.com/go-jose/go-jose/v4 v4.1.4/go.mod h1:x4oUasVrzR7071A4TnHLGSPpNOm2a21K9Kf04k1rs08=
+github.com/go-ldap/ldap/v3 v3.4.15 h1:eRB4f4Ecn1POL1mO86+uUDlecmyWsdiJwh60bAUS4UY=
+github.com/go-ldap/ldap/v3 v3.4.15/go.mod h1:jeD0c98EdZQCKKKKe4kTWs5aCf6y+j8KuYsYLznZSQk=
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/logr v1.4.4 h1:tG4xh9yMsRCAiodLVTxyrkzSZ9+o0L1Kg/+cPVcbP/8=
 github.com/go-logr/logr v1.4.4/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
@@ -69,6 +77,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.30.0 h1:/Tnpcb2E0Pz/tN9s3bfEY2Q8ePCEX9iuS+cneUwncnw=
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.30.0/go.mod h1:zOBXOsUaBSjKgmH4OGzV1esUpR3oUSCPYVd2cUBjKYY=
+github.com/hashicorp/go-uuid v1.0.3 h1:2gKiV6YVmrJ1i2CKKa9obLvRieoRGviZFL26PcT/Co8=
+github.com/hashicorp/go-uuid v1.0.3/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
@@ -81,6 +91,18 @@ github.com/jackc/pgx/v5 v5.11.0 h1:IzBBtyK9AHqf98cctWFifYSci2hgQR/cd56wB4p+ogg=
 github.com/jackc/pgx/v5 v5.11.0/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
 github.com/jackc/puddle/v2 v2.2.2 h1:PR8nw+E/1w0GLuRFSmiioY6UooMp6KJv0/61nB7icHo=
 github.com/jackc/puddle/v2 v2.2.2/go.mod h1:vriiEXHvEE654aYKXXjOvZM39qJ0q+azkZFrfEOc3H4=
+github.com/jcmturner/aescts/v2 v2.0.0 h1:9YKLH6ey7H4eDBXW8khjYslgyqG2xZikXP0EQFKrle8=
+github.com/jcmturner/aescts/v2 v2.0.0/go.mod h1:AiaICIRyfYg35RUkr8yESTqvSy7csK90qZ5xfvvsoNs=
+github.com/jcmturner/dnsutils/v2 v2.0.0 h1:lltnkeZGL0wILNvrNiVCR6Ro5PGU/SeBvVO/8c/iPbo=
+github.com/jcmturner/dnsutils/v2 v2.0.0/go.mod h1:b0TnjGOvI/n42bZa+hmXL+kFJZsFT7G4t3HTlQ184QM=
+github.com/jcmturner/gofork v1.7.6 h1:QH0l3hzAU1tfT3rZCnW5zXl+orbkNMMRGJfdJjHVETg=
+github.com/jcmturner/gofork v1.7.6/go.mod h1:1622LH6i/EZqLloHfE7IeZ0uEJwMSUyQ/nDd82IeqRo=
+github.com/jcmturner/goidentity/v6 v6.0.1 h1:VKnZd2oEIMorCTsFBnJWbExfNN7yZr3EhJAxwOkZg6o=
+github.com/jcmturner/goidentity/v6 v6.0.1/go.mod h1:X1YW3bgtvwAXju7V3LCIMpY0Gbxyjn/mY9zx4tFonSg=
+github.com/jcmturner/gokrb5/v8 v8.4.4 h1:x1Sv4HaTpepFkXbt2IkL29DXRf8sOfZXo8eRKh687T8=
+github.com/jcmturner/gokrb5/v8 v8.4.4/go.mod h1:1btQEpgT6k+unzCwX1KdWMEwPPkkgBtP+F6aCACiMrs=
+github.com/jcmturner/rpc/v2 v2.0.3 h1:7FXXj8Ti1IaVFpSAziCZWNzbNuZmnvw/i6CqLNdWfZY=
+github.com/jcmturner/rpc/v2 v2.0.3/go.mod h1:VUJYCIDm3PVOEHw8sgt091/20OJjskO/YJki3ELg/Hc=
 github.com/klauspost/compress v1.19.1 h1:VsB4HPswih7mmZ8WleSFQ75c/Ui1M4trX5oAsJnhSlk=
 github.com/klauspost/compress v1.19.1/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
 github.com/knadh/koanf/maps v0.1.2 h1:RBfmAW5CnZT+PJ1CVc1QSJKf4Xu9kxfQgYVQSu8hpbo=

internal/account/directory_test.go

@@ -0,0 +1,63 @@
+package account
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
+)
+
+type fakeDirectory struct {
+	asked []string
+	u     store.User
+	err   error
+}
+
+func (f *fakeDirectory) SignIn(_ context.Context, login, _ string) (store.User, error) {
+	f.asked = append(f.asked, login)
+	return f.u, f.err
+}
+
+// With a directory, a name the store has no password for is the
+// directory's to check; an account with a password here — the
+// administrator init made — is still checked here, so a directory that is
+// down locks nobody out.
+func TestPasswordsKeptElsewhereAreTheDirectorysToCheck(t *testing.T) {
+	svc, st := newService(t)
+	ctx := t.Context()
+	hash, _ := HashPassword("local-secret")
+	admin := store.User{ID: "usr-admin", Email: "admin@example.com", Name: "a", PasswordHash: hash,
+		State: store.UserActive, CreatedAt: time.Now()}
+	ada := store.User{ID: "usr-ada", Email: "ada@corp.example", Name: "Ada", PasswordHash: "!ldap",
+		State: store.UserActive, CreatedAt: time.Now()}
+	for _, u := range []store.User{admin, ada} {
+		if err := st.CreateUser(ctx, u); err != nil {
+			t.Fatal(err)
+		}
+	}
+	dir := &fakeDirectory{u: ada}
+	svc.SetDirectory(dir)
+
+	if _, _, err := svc.SignIn(ctx, "admin@example.com", "local-secret"); err != nil || len(dir.asked) != 0 {
+		t.Fatalf("the local administrator: %v, directory asked %v", err, dir.asked)
+	}
+	// A name, not an address, and an account kept by the directory.
+	for _, login := range []string{`CORP\ada`, "ada@corp.example"} {
+		if tok, _, err := svc.SignIn(ctx, login, "ad-secret"); err != nil || tok == "" {
+			t.Errorf("%s: %v", login, err)
+		}
+	}
+	if len(dir.asked) != 2 || dir.asked[0] != `CORP\ada` {
+		t.Errorf("the directory was asked %v", dir.asked)
+	}
+	dir.err = ErrBadCredentials
+	if _, _, err := svc.SignIn(ctx, "ada", "wrong"); !errors.Is(err, ErrBadCredentials) {
+		t.Errorf("a password the directory refused: %v", err)
+	}
+	// A reset link would give a directory's account a password here.
+	if _, _, err := svc.RequestReset(ctx, st, "ada@corp.example"); !errors.Is(err, ErrNoReset) {
+		t.Errorf("a directory's account was sent a reset link: %v", err)
+	}
+}

internal/account/service.go

@@ -80,8 +80,26 @@ type Service struct {
 
 	mu       sync.Mutex
 	attempts map[string]*attemptWindow
+
+	// dir checks the passwords of accounts this store keeps none for.
+	dir Directory
 }
 
+// Directory checks a password against an outside directory — Active
+// Directory over LDAP — and answers the account to sign in: made or kept in
+// step with the directory. Its errors are this package's ErrBadCredentials
+// and ErrSuspended for the person's own, and anything else for the
+// directory's.
+type Directory interface {
+	SignIn(ctx context.Context, login, password string) (store.User, error)
+}
+
+// SetDirectory has passwords for accounts with none here, and names that are
+// not addresses, checked by the directory. An account with a password here
+// — the administrator init made — is still checked here, so a directory that
+// is down locks nobody out.
+func (s *Service) SetDirectory(d Directory) { s.dir = d }
+
 type attemptWindow struct {
 	count int
 	since time.Time
@@ -137,6 +155,7 @@ func (s *Service) SignUp(ctx context.Context, email, name, password string) erro
 // SignIn checks a password and opens a session, returning the session token and
 // the CSRF token that must accompany the forms in it.
 func (s *Service) SignIn(ctx context.Context, email, password string) (token, csrf string, err error) {
+	login := strings.TrimSpace(email)
 	email = store.NormalizeEmail(email)
 	// Counted per address and the client trying it, so somebody guessing
 	// from elsewhere cannot lock the owner out of their own account; and per
@@ -151,6 +170,15 @@ func (s *Service) SignIn(ctx context.Context, email, password string) (token, cs
 	}
 
 	u, err := s.store.UserByEmail(ctx, email)
+	// No password kept here — the directory's, or nobody's — and a
+	// directory to ask: it decides.
+	if s.dir != nil && (errors.Is(err, store.ErrNotFound) || (err == nil && strings.HasPrefix(u.PasswordHash, "!"))) {
+		if u, err = s.dir.SignIn(ctx, login, password); err != nil {
+			return "", "", err
+		}
+		s.clearAttempts(byClient)
+		return s.open(ctx, u)
+	}
 	if errors.Is(err, store.ErrNotFound) {
 		// Verify anyway, against a hash that cannot match. Returning early here
 		// would let a stopwatch enumerate every account on the system.
@@ -180,7 +208,11 @@ func (s *Service) SignIn(ctx context.Context, email, password string) (token, cs
 	case store.UserSuspended:
 		return "", "", ErrSuspended
 	}
+	return s.open(ctx, u)
+}
 
+// open makes a session for a person whose password was right.
+func (s *Service) open(ctx context.Context, u store.User) (token, csrf string, err error) {
 	if token, err = store.NewSessionToken(); err != nil {
 		return "", "", err
 	}
@@ -402,7 +434,10 @@ func (s *Service) RequestReset(ctx context.Context, rs ResetStore, email string)
 		return "", store.User{}, ErrTooManyTries
 	}
 	u, err := rs.UserByEmail(ctx, email)
-	if err != nil || u.PasswordHash == "" || u.State != store.UserActive {
+	// An account whose password is kept elsewhere — "!oidc", "!scim",
+	// "!ldap" — gets no link: setting one here would give it a second way
+	// in that its directory knows nothing of, and outlives its leaving.
+	if err != nil || u.PasswordHash == "" || strings.HasPrefix(u.PasswordHash, "!") || u.State != store.UserActive {
 		return "", store.User{}, ErrNoReset
 	}
 	token, err := rs.CreatePasswordReset(ctx, u.ID, ResetLinkTTL)

internal/accounting/accounting.go

@@ -323,7 +323,7 @@ func (a *Accountant) Record(res Reservation, u store.Usage) {
 	if u.ServedModel != "" && u.ServedModel != u.Model && a.pricing != nil {
 		price = a.pricing.For(u.ServedModel)
 	}
-	u.CostMicros = price.Cost(u.PromptTokens, u.CompletionTokens, u.Images, u.Meshes)
+	u.CostMicros = price.Cost(u.PromptTokens, u.CachedTokens, u.CompletionTokens, u.Images, u.Meshes)
 	for _, b := range res.Budgets {
 		a.budgets.Add(b.Counter, b.Period, u.CostMicros)
 	}

internal/accounting/accounting_test.go

@@ -39,20 +39,37 @@ func TestCostRoundsUpSoSmallRequestsAreNotFree(t *testing.T) {
 	// Rounding down would make a stream of tiny requests cost nothing, which is
 	// exactly the traffic shape a quota exists to bound.
 	p := Price{PromptPer1k: 1000, CompletionPer1k: 3000}
-	if got := p.Cost(1, 0, 0, 0); got != 1 {
+	if got := p.Cost(1, 0, 0, 0, 0); got != 1 {
 		t.Errorf("one prompt token cost %d", got)
 	}
-	if got := p.Cost(1000, 1000, 0, 0); got != 4000 {
+	if got := p.Cost(1000, 0, 1000, 0, 0); got != 4000 {
 		t.Errorf("a thousand of each cost %d, want 4000", got)
 	}
-	if got := p.Cost(0, 0, 0, 0); got != 0 {
+	if got := p.Cost(0, 0, 0, 0, 0); got != 0 {
 		t.Errorf("an empty request cost %d", got)
 	}
 }
 
+func TestACachedPromptCostsTheCachedRate(t *testing.T) {
+	p := Price{PromptPer1k: 1000, CachedPer1k: 100, CompletionPer1k: 3000}
+	// 10,000 prompt tokens of which 9,000 were read from the cache: 1,000 at
+	// the prompt rate and 9,000 at the cached one.
+	if got, want := p.Cost(10000, 9000, 0, 0, 0), int64(1000+900); got != want {
+		t.Errorf("a 90%% cached prompt cost %d, want %d", got, want)
+	}
+	// More cached than prompt is an engine's miscount, not a refund.
+	if got := p.Cost(100, 500, 0, 0, 0); got != 10 {
+		t.Errorf("cached beyond the prompt cost %d, want 10", got)
+	}
+	// No cached rate: cached tokens cost what any prompt token does.
+	if got := (Price{PromptPer1k: 1000}).Cost(10000, 9000, 0, 0, 0); got != 10000 {
+		t.Errorf("without a cached rate a cached prompt cost %d, want 10000", got)
+	}
+}
+
 func TestAPictureCostsItsPriceOnTopOfItsPrompt(t *testing.T) {
 	p := Price{PromptPer1k: 1000, PerImage: 50000}
-	if got := p.Cost(20, 0, 3, 0); got != 20+150000 {
+	if got := p.Cost(20, 0, 0, 3, 0); got != 20+150000 {
 		t.Errorf("three pictures from a 20-token prompt cost %d", got)
 	}
 	if (Price{PerImage: 1}).Zero() {

internal/accounting/cost.go

@@ -18,6 +18,11 @@ import (
 type Price struct {
 	PromptPer1k     int64 `koanf:"prompt_per_1k"`
 	CompletionPer1k int64 `koanf:"completion_per_1k"`
+	// CachedPer1k is what a prompt token costs that the engine or provider
+	// read from its cache instead of computing: the part of prompt_tokens
+	// the answer counts as cached_tokens. Zero charges those at
+	// PromptPer1k, as before there was a rate for them.
+	CachedPer1k int64 `koanf:"cached_per_1k"`
 	// PerImage is what one picture costs, for a model that makes them: a
 	// picture's cost is the card's time, which its prompt's few tokens do
 	// not measure.
@@ -33,15 +38,24 @@ type Price struct {
 // whose budget is spent, which is what makes the plan's budget fallback work
 // (§7.7).
 func (p Price) Zero() bool {
-	return p.PromptPer1k == 0 && p.CompletionPer1k == 0 && p.PerImage == 0 && p.PerMesh == 0
+	return p.PromptPer1k == 0 && p.CompletionPer1k == 0 && p.CachedPer1k == 0 && p.PerImage == 0 && p.PerMesh == 0
 }
 
 // Cost computes what a request spent, rounding up.
 //
 // Up rather than to nearest: rounding down would make a stream of tiny requests
 // free, which is exactly the shape of traffic a quota exists to bound.
-func (p Price) Cost(promptTokens, completionTokens, images, meshes int64) int64 {
-	return divUp(promptTokens*p.PromptPer1k, 1000) + divUp(completionTokens*p.CompletionPer1k, 1000) +
+//
+// cachedTokens are counted within promptTokens, as OpenAI's usage counts
+// them, and are charged at the cached rate instead of the prompt rate.
+func (p Price) Cost(promptTokens, cachedTokens, completionTokens, images, meshes int64) int64 {
+	cachedTokens = min(max(cachedTokens, 0), max(promptTokens, 0))
+	cachedRate := p.CachedPer1k
+	if cachedRate == 0 {
+		cachedRate = p.PromptPer1k
+	}
+	return divUp((promptTokens-cachedTokens)*p.PromptPer1k+cachedTokens*cachedRate, 1000) +
+		divUp(completionTokens*p.CompletionPer1k, 1000) +
 		max(images, 0)*p.PerImage + max(meshes, 0)*p.PerMesh
 }
 

internal/agent/agent.go

@@ -12,6 +12,7 @@ import (
 	"io"
 	"log/slog"
 	"maps"
+	"math"
 	"math/rand/v2"
 	"net"
 	"net/http"
@@ -46,7 +47,9 @@ import (
 
 // Agent runs on a GPU node.
 type Agent struct {
-	cfg Config
+	// upgrading is true while an upgrade downloads.
+	upgrading atomic.Bool
+	cfg       Config
 	// answered says the current session heard from its control plane, which
 	// starts the reconnect backoff again when it ends.
 	answered atomic.Bool
@@ -392,8 +395,11 @@ func (a *Agent) settleAdopted(sh *supervisor.Shard, o supervisor.Orphan) {
 		_ = a.sup.Stop(ctx, o.ShardID)
 		return
 	}
-	// What it computes on, for one started before the agent kept that.
-	if a.sup.ComputeOf(o.ShardID) == nil {
+	// What it computes on, for one started before the agent kept that — or
+	// kept as the CPU for a GPU placement by an agent that did not follow
+	// an engine into a process group of its own, which the check above has
+	// just found on its GPUs.
+	if c := a.sup.ComputeOf(o.ShardID); c == nil || (len(o.Spec.GPUIndices) > 0 && c.Backend == "CPU") {
 		if c, ok := a.gpuCompute(ctx, o.Spec.GPUIndices, sh.Status().PID); ok {
 			a.sup.SetCompute(o.ShardID, c)
 		}
@@ -513,6 +519,7 @@ func (a *Agent) scan(ctx context.Context) error {
 	inv, err := discovery.Discover(ctx, opts, a.log)
 	host := discovery.DiscoverHost()
 	host.MinComputeCapability = discovery.MinComputeCapability(inv.GPUs)
+	host.MemBandwidthGBs = a.memBandwidth()
 	a.mu.Lock()
 	a.inv = inv
 	a.prov.Host = host
@@ -569,6 +576,9 @@ func (a *Agent) session(ctx context.Context, server string) error {
 	reg.Host = &llmgwv1.Host{
 		OsId: h.OSID, OsVersion: h.OSVersion, OsCodename: h.OSCodename,
 		Arch: h.Arch, CpuFlags: h.CPUFlags, NvidiaDriver: h.NVIDIADriver,
+		// What is measured by now, not what the startup scan found before
+		// the measurement ended: a reconnect would otherwise say 0.
+		MemBandwidthGbs: a.memBandwidth(),
 	}
 
 	if err := stream.Send(&llmgwv1.AgentMessage{
@@ -666,6 +676,7 @@ func (a *Agent) heartbeat() *llmgwv1.AgentMessage {
 	// without anybody restarting anything.
 	hb.MemoryTotalMb = int64(discovery.MemoryTotalMB())
 	hb.CpuCount = int32(runtime.NumCPU())
+	hb.MemBandwidthGbs = a.memBandwidth()
 
 	a.reprobeEngines()
 	a.mu.Lock()
@@ -869,6 +880,7 @@ func (a *Agent) removeWeights(paths []string) {
 			a.log.Warn("could not remove cached weights", "path", p, "err", err)
 			continue
 		}
+		_ = os.Remove(weights.ChecksumPath(abs))
 		a.log.Info("removed cached weights no model asks for", "path", p)
 	}
 }
@@ -1124,7 +1136,7 @@ func (a *Agent) startShard(ctx context.Context, m *llmgwv1.StartShard, out chan<
 			},
 		})
 	})
-	if path, err := a.weights().Ensure(ctx, spec.Profile.ModelPath); err != nil {
+	if path, err := a.weights().EnsureChecked(ctx, spec.Profile.ModelPath, spec.Profile.AllowPickle, spec.Profile.ModelSHA256); err != nil {
 		stop()
 		report(supervisor.Failed, err.Error(), nil)
 		return
@@ -1145,7 +1157,7 @@ func (a *Agent) startShard(ctx context.Context, m *llmgwv1.StartShard, out chan<
 				send(&llmgwv1.ShardStatus{State: agentsvc.StateToWire(supervisor.Starting),
 					Fetch: &llmgwv1.FetchProgress{Source: p.Source, BytesDone: p.BytesDone, BytesTotal: p.BytesTotal}})
 			})
-			path, err := a.weights().Ensure(ctx, m["source"])
+			path, err := a.weights().Ensure(ctx, m["source"], m["allow_pickle"] == "true")
 			stop()
 			if err != nil {
 				report(supervisor.Failed, fmt.Sprintf("model %s: %v", m["name"], err), nil)
@@ -1161,7 +1173,7 @@ func (a *Agent) startShard(ctx context.Context, m *llmgwv1.StartShard, out chan<
 	// loads them at start, and one missing is a replica that answers for the
 	// base model under the adapter's name.
 	for i, ad := range spec.Profile.Adapters {
-		path, err := a.weights().Ensure(ctx, ad.Path)
+		path, err := a.weights().Ensure(ctx, ad.Path, spec.Profile.AllowPickle)
 		if err != nil {
 			report(supervisor.Failed, fmt.Sprintf("adapter %s: %v", ad.Name, err), nil)
 			return
@@ -1505,18 +1517,25 @@ func ResolveManagement(c Config) (addr, iface string) {
 // shard computes on as soon as that is known: an adopted engine's is found
 // after registration, which carried what was known then.
 func (a *Agent) reportCompute(ctx context.Context, out chan<- *llmgwv1.AgentMessage) {
-	sent := map[string]bool{}
+	// What was sent for each shard, so a compute that changes is sent again:
+	// an adopted shard's kept one is sent at once, and adopting it may then
+	// find it was kept wrong.
+	sent := map[string]string{}
 	t := time.NewTicker(5 * time.Second)
 	defer t.Stop()
 	for range 60 {
 		for _, st := range a.sup.Statuses() {
-			if st.State.Terminal() || sent[st.ID] {
+			if st.State.Terminal() {
 				continue
 			}
 			c := a.sup.ComputeOf(st.ID)
 			if c == nil {
 				continue
 			}
+			said := fmt.Sprint(*c)
+			if sent[st.ID] == said {
+				continue
+			}
 			sh, err := a.sup.Get(st.ID)
 			if err != nil {
 				continue
@@ -1527,7 +1546,7 @@ func (a *Agent) reportCompute(ctx context.Context, out chan<- *llmgwv1.AgentMess
 			}}}
 			select {
 			case out <- msg:
-				sent[st.ID] = true
+				sent[st.ID] = said
 			case <-ctx.Done():
 				return
 			}
@@ -1539,3 +1558,38 @@ func (a *Agent) reportCompute(ctx context.Context, out chan<- *llmgwv1.AgentMess
 		}
 	}
 }
+
+// memBandwidth is the node's memory read rate in GB/s, 0 until measured.
+// Measured in the background, the first time it is asked for: it reads half
+// a gigabyte, which must not hold up an agent reaching its control plane,
+// and the heartbeat carries it when it is known. Not at once but after a
+// minute or so, chosen at random, and again every hour, keeping the best:
+// VMs on one host that all restart together measure each other, and read a
+// third less than any of them gets alone. Once a process rather than an
+// agent, so tests running many agents in one read it once.
+func (a *Agent) memBandwidth() float64 {
+	bwOnce.Do(func() {
+		go func() {
+			time.Sleep(bandwidthDelay())
+			for {
+				if bw := measureBandwidth(); bw > math.Float64frombits(bwBits.Load()) {
+					bwBits.Store(math.Float64bits(bw))
+					a.log.Info("this node's memory", "read_gbs", math.Round(bw*10)/10)
+				}
+				time.Sleep(time.Hour)
+			}
+		}()
+	})
+	return math.Float64frombits(bwBits.Load())
+}
+
+// bandwidthDelay is how long an agent waits before measuring, so agents
+// started together measure apart.
+var bandwidthDelay = func() time.Duration { return 10*time.Second + rand.N(110*time.Second) }
+
+var (
+	bwOnce sync.Once
+	bwBits atomic.Uint64
+	// measureBandwidth is replaced in tests, which have no use for it.
+	measureBandwidth = discovery.MeasureMemoryBandwidth
+)

internal/agent/agent_test.go

@@ -671,7 +671,7 @@ func TestAShardWithMissingWeightsFailsBeforeLaunching(t *testing.T) {
 	// nobody is watching — so it is caught here, where the message can say
 	// what is actually wrong.
 	a := &Agent{cfg: Config{WeightsCache: t.TempDir()}, log: slog.New(slog.DiscardHandler)}
-	_, err := a.weights().Ensure(t.Context(), filepath.Join(t.TempDir(), "not-there.gguf"))
+	_, err := a.weights().Ensure(t.Context(), filepath.Join(t.TempDir(), "not-there.gguf"), false)
 	if err == nil {
 		t.Fatal("a missing weights file was accepted")
 	}

internal/agent/discovery/gpu.go

@@ -52,6 +52,8 @@ type GPU struct {
 	// memory the instance's share. Utilisation stays unreported, because no
 	// driver measures it per instance.
 	MIG *MIGDevice `json:"mig,omitempty"`
+	// PCIe is how the card is linked to its host, zero when not read.
+	PCIe PCIeLink `json:"pcie,omitempty"`
 }
 
 // GPUHealth records conditions that make a GPU unsafe to schedule onto.

internal/agent/discovery/gpu_nvml.go

@@ -67,10 +67,23 @@ func DiscoverGPUsNVML(_ context.Context) ([]GPU, error) {
 		if major, minor, ret := dev.GetCudaComputeCapability(); ret == nvml.SUCCESS {
 			g.ComputeCapability = fmt.Sprintf("%d.%d", major, minor)
 		}
+		if v, ret := dev.GetMaxPcieLinkGeneration(); ret == nvml.SUCCESS {
+			g.PCIe.Gen = v
+		}
+		if v, ret := dev.GetGpuMaxPcieLinkGeneration(); ret == nvml.SUCCESS {
+			g.PCIe.GPUGen = v
+		}
+		if v, ret := dev.GetCurrPcieLinkWidth(); ret == nvml.SUCCESS {
+			g.PCIe.Width = v
+		}
+		if v, ret := dev.GetMaxPcieLinkWidth(); ret == nvml.SUCCESS {
+			g.PCIe.WidthMax = v
+		}
 		if pci, ret := dev.GetPciInfo(); ret == nvml.SUCCESS {
 			g.PCIBusID = busIDString(pci.BusId[:])
 			byBusID[normalizeBusID(g.PCIBusID)] = i
 		}
+		g.PCIe = withSysfs(g.PCIe, "/sys/bus/pci/devices", g.PCIBusID)
 		if t, ret := dev.GetTemperature(nvml.TEMPERATURE_GPU); ret == nvml.SUCCESS {
 			g.Health.TemperatureC = int(t)
 		}

internal/agent/discovery/gpu_smi.go

@@ -64,6 +64,7 @@ func DiscoverGPUsSMI(ctx context.Context, binary string) ([]GPU, error) {
 	if err != nil || len(cards) == 0 {
 		return cards, err
 	}
+	readPCIe(ctx, binary, cards)
 	// The query lists whole cards, MIG mode or not. A card in MIG mode is
 	// replaced by its instances, which only -L names and only the full
 	// report sizes; asked only when some card could be in MIG mode, since

internal/agent/discovery/host.go

@@ -31,6 +31,10 @@ type Host struct {
 	// MinComputeCapability is the oldest GPU's, 0 when there are none or it
 	// is not known. Not read here but from the GPU inventory, by the agent.
 	MinComputeCapability float64 `json:"min_compute_capability,omitempty"`
+	// MemBandwidthGBs is how fast the memory reads, in GB/s, 0 when not
+	// measured: what decides a model's speed on the CPU. Not read here but
+	// measured by the agent when it starts (MeasureMemoryBandwidth).
+	MemBandwidthGBs float64 `json:"mem_bandwidth_gbs,omitempty"`
 }
 
 // Family is the packaging family: "deb", "rpm", or "" when neither is known.

internal/agent/discovery/membw.go

@@ -0,0 +1,146 @@
+package discovery
+
+import (
+	"bufio"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// How fast this machine reads its memory, which on a CPU is what decides how
+// fast a model answers: every token of a reply reads all the weights it uses
+// once, so a node that reads 40 GB/s writes a 4 GB model's tokens about ten
+// times a second, whatever its core count. Measured once when the agent
+// starts, in a fraction of a second, by every CPU summing a share of a buffer
+// too large for any cache — a VM sharing its host's memory with others gets
+// its share, which is the number that matters for it.
+
+// bandwidthBuffer is what is read at most; the least is eight times the
+// processor's last cache, and never under minBuffer. Smaller, it would be
+// the cache that was measured — some hold a gigabyte — and the figure kept
+// would be too high.
+const (
+	bandwidthBuffer = 2 << 30
+	minBuffer       = 256 << 20
+)
+
+// MeasureMemoryBandwidth is the memory's read rate in GB/s, the best of a
+// few passes; 0 when the machine has too little free memory to measure.
+func MeasureMemoryBandwidth() float64 {
+	size := int64(bandwidthBuffer)
+	// Never more than a quarter of what is free: a node already holding
+	// models must not be pushed into swap by a measurement. Without room
+	// for a buffer past the cache, none is measured: the hourly retry
+	// measures it when there is.
+	if avail := memAvailable("/proc/meminfo"); avail > 0 {
+		size = min(size, avail/4)
+	}
+	if size < max(minBuffer, 8*lastCacheBytes("/sys/devices/system/cpu")) {
+		return 0
+	}
+	buf := make([]uint64, size/8)
+	for i := range buf {
+		buf[i] = uint64(i)
+	}
+	workers := runtime.NumCPU()
+	chunk := (len(buf) + workers - 1) / workers
+	best := 0.0
+	for pass := 0; pass < 4; pass++ {
+		var wg sync.WaitGroup
+		start := time.Now()
+		for w := 0; w < workers; w++ {
+			lo, hi := w*chunk, min((w+1)*chunk, len(buf))
+			if lo >= hi {
+				continue
+			}
+			wg.Add(1)
+			go func(part []uint64) {
+				defer wg.Done()
+				sink(sum(part))
+			}(buf[lo:hi])
+		}
+		wg.Wait()
+		if s := time.Since(start).Seconds(); s > 0 {
+			best = max(best, float64(size)/s/1e9)
+		}
+	}
+	return best
+}
+
+// sum reads every word, eight at a time so the loop is not what limits it.
+func sum(p []uint64) uint64 {
+	var a, b, c, d, e, f, g, h uint64
+	i := 0
+	for ; i+8 <= len(p); i += 8 {
+		a += p[i]
+		b += p[i+1]
+		c += p[i+2]
+		d += p[i+3]
+		e += p[i+4]
+		f += p[i+5]
+		g += p[i+6]
+		h += p[i+7]
+	}
+	for ; i < len(p); i++ {
+		a += p[i]
+	}
+	return a + b + c + d + e + f + g + h
+}
+
+// sinkValue keeps the sums alive, so the reads are not optimised away.
+var sinkValue struct {
+	sync.Mutex
+	v uint64
+}
+
+func sink(v uint64) {
+	sinkValue.Lock()
+	sinkValue.v += v
+	sinkValue.Unlock()
+}
+
+// memAvailable is MemAvailable in bytes, 0 when unknown.
+func memAvailable(path string) int64 {
+	f, err := os.Open(path) //nolint:gosec // a fixed system path
+	if err != nil {
+		return 0
+	}
+	defer f.Close()
+	sc := bufio.NewScanner(f)
+	for sc.Scan() {
+		fields := strings.Fields(sc.Text())
+		if len(fields) >= 2 && fields[0] == "MemAvailable:" {
+			kb, _ := strconv.ParseInt(fields[1], 10, 64)
+			return kb << 10
+		}
+	}
+	return 0
+}
+
+// lastCacheBytes is the largest cache any CPU reports, 0 when unknown.
+func lastCacheBytes(root string) int64 {
+	paths, _ := filepath.Glob(filepath.Join(root, "cpu*", "cache", "index*", "size"))
+	var most int64
+	for _, p := range paths {
+		b, err := os.ReadFile(p) //nolint:gosec // under /sys
+		if err != nil {
+			continue
+		}
+		v := strings.TrimSpace(string(b))
+		mult := int64(1)
+		switch {
+		case strings.HasSuffix(v, "K"):
+			mult, v = 1<<10, strings.TrimSuffix(v, "K")
+		case strings.HasSuffix(v, "M"):
+			mult, v = 1<<20, strings.TrimSuffix(v, "M")
+		}
+		if n, err := strconv.ParseInt(v, 10, 64); err == nil {
+			most = max(most, n*mult)
+		}
+	}
+	return most
+}

internal/agent/discovery/membw_test.go

@@ -0,0 +1,32 @@
+package discovery
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestMemoryBandwidthIsMeasured(t *testing.T) {
+	if testing.Short() {
+		t.Skip("reads half a gigabyte")
+	}
+	bw := MeasureMemoryBandwidth()
+	// Any machine running this reads more than a gigabyte a second and less
+	// than a few terabytes.
+	if bw < 1 || bw > 5000 {
+		t.Errorf("measured %.1f GB/s", bw)
+	}
+	t.Logf("%.1f GB/s", bw)
+}
+
+func TestTheLastCacheIsReadFromSys(t *testing.T) {
+	root := t.TempDir()
+	for path, size := range map[string]string{"cpu0/cache/index0/size": "48K", "cpu0/cache/index3/size": "96M"} {
+		p := filepath.Join(root, path)
+		_ = os.MkdirAll(filepath.Dir(p), 0o755)
+		_ = os.WriteFile(p, []byte(size+"\n"), 0o644)
+	}
+	if got := lastCacheBytes(root); got != 96<<20 {
+		t.Errorf("%d", got)
+	}
+}

internal/agent/discovery/pcie.go

@@ -0,0 +1,181 @@
+package discovery
+
+import (
+	"context"
+	"encoding/csv"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+)
+
+// A card in the wrong slot: an x16 card in a slot wired x8 or x4, behind a
+// riser, or in a slot of an older PCIe generation than the card's, links
+// slower than it was built to, and nothing says so. A model on the card
+// still decodes at the card's own memory speed, but it loads slower, a
+// tensor-parallel replica over PCIe is slower, and so is anything that
+// spills to the host. The driver says how the link stands and what the
+// card could do; the difference is reported where the node's warnings are.
+
+// PCIeLink is how a card is linked to its host.
+type PCIeLink struct {
+	// Gen is the fastest generation the card and the slot together allow —
+	// not the current one, which drops while the card idles, to save power.
+	// GPUGen is the card's own fastest, 0 when the driver does not say.
+	Gen    int `json:"gen,omitempty"`
+	GPUGen int `json:"gpu_gen,omitempty"`
+	// Width is the lanes in use now, WidthMax the card's most.
+	Width    int `json:"width,omitempty"`
+	WidthMax int `json:"width_max,omitempty"`
+}
+
+// laneGBs is one lane's usable rate in GB/s, by generation.
+var laneGBs = map[int]float64{1: 0.25, 2: 0.5, 3: 0.985, 4: 1.969, 5: 3.938, 6: 7.877}
+
+// GBs is what a link of gen and width carries, in GB/s each way.
+func pcieGBs(gen, width int) float64 { return laneGBs[gen] * float64(width) }
+
+// Problem says how a card's link falls short of what the card could do,
+// empty when it does not or the driver did not say.
+func (p PCIeLink) Problem() string {
+	gen := p.Gen
+	if p.GPUGen > 0 && gen == 0 {
+		gen = p.GPUGen
+	}
+	slowGen := p.GPUGen > 0 && p.Gen > 0 && p.Gen < p.GPUGen
+	narrow := p.WidthMax > 0 && p.Width > 0 && p.Width < p.WidthMax
+	if !slowGen && !narrow {
+		return ""
+	}
+	could := pcieGBs(max(p.GPUGen, gen), p.WidthMax)
+	has := pcieGBs(gen, p.Width)
+	var why []string
+	if narrow {
+		why = append(why, fmt.Sprintf("x%d of its x%d lanes", p.Width, p.WidthMax))
+	}
+	if slowGen {
+		why = append(why, fmt.Sprintf("PCIe Gen%d of its Gen%d", p.Gen, p.GPUGen))
+	}
+	return fmt.Sprintf("linked at %s: %.1f GB/s where it could have %.1f. "+
+		"Check the slot (wired fewer lanes, or an older generation), a riser, or the BIOS's PCIe setting",
+		strings.Join(why, " and "), has, could)
+}
+
+// pcieFields are asked apart from the rest, and the card's own fastest
+// generation apart again: a driver that does not know a field refuses the
+// whole query, and these must not cost a node its cards.
+var pcieFields = [][]string{
+	{"index", "pcie.link.gen.max", "pcie.link.width.current", "pcie.link.width.max", "pcie.link.gen.gpumax"},
+	{"index", "pcie.link.gen.max", "pcie.link.width.current", "pcie.link.width.max"},
+}
+
+// readPCIe fills each card's link from nvidia-smi, leaving it empty when
+// the driver says nothing of it.
+func readPCIe(ctx context.Context, binary string, cards []GPU) {
+	for _, fields := range pcieFields {
+		out, err := exec.CommandContext(ctx, binary, "--query-gpu="+strings.Join(fields, ","),
+			"--format=csv,noheader,nounits").Output()
+		if err != nil {
+			continue
+		}
+		links := parsePCIe(string(out))
+		for i := range cards {
+			if l, ok := links[cards[i].Index]; ok && cards[i].MIG == nil {
+				cards[i].PCIe = l
+			}
+		}
+		break
+	}
+	for i := range cards {
+		if cards[i].MIG == nil {
+			cards[i].PCIe = withSysfs(cards[i].PCIe, "/sys/bus/pci/devices", cards[i].PCIBusID)
+		}
+	}
+}
+
+// withSysfs takes the card's own lane count, and its own fastest
+// generation, from the kernel: the driver's width.max is what card and slot
+// allow together, so a x16 card in a slot wired x8 reads x8 of x8 there,
+// while the device's max_link_width is the card's, 16.
+func withSysfs(l PCIeLink, root, busID string) PCIeLink {
+	dev := sysfsBusID(busID)
+	if dev == "" {
+		return l
+	}
+	read := func(name string) string {
+		b, err := os.ReadFile(filepath.Join(root, dev, name)) //nolint:gosec // under /sys
+		if err != nil {
+			return ""
+		}
+		return strings.TrimSpace(string(b))
+	}
+	if n, err := strconv.Atoi(read("max_link_width")); err == nil && n > 0 {
+		l.WidthMax = n
+	}
+	if n, err := strconv.Atoi(read("current_link_width")); err == nil && n > 0 {
+		l.Width = n
+	}
+	if g := genOfSpeed(read("max_link_speed")); g > 0 && l.GPUGen == 0 {
+		l.GPUGen = g
+	}
+	return l
+}
+
+// sysfsBusID is nvidia-smi's 00000000:3B:00.0 as the kernel names it,
+// 0000:3b:00.0.
+func sysfsBusID(id string) string {
+	id = strings.ToLower(strings.TrimSpace(id))
+	dom, rest, ok := strings.Cut(id, ":")
+	if !ok || len(dom) < 4 {
+		return ""
+	}
+	return dom[len(dom)-4:] + ":" + rest
+}
+
+// genOfSpeed is the PCIe generation of a link speed as sysfs writes it.
+func genOfSpeed(s string) int {
+	switch {
+	case strings.HasPrefix(s, "2.5 GT/s"):
+		return 1
+	case strings.HasPrefix(s, "5.0 GT/s"), strings.HasPrefix(s, "5 GT/s"):
+		return 2
+	case strings.HasPrefix(s, "8.0 GT/s"), strings.HasPrefix(s, "8 GT/s"):
+		return 3
+	case strings.HasPrefix(s, "16.0 GT/s"), strings.HasPrefix(s, "16 GT/s"):
+		return 4
+	case strings.HasPrefix(s, "32.0 GT/s"), strings.HasPrefix(s, "32 GT/s"):
+		return 5
+	case strings.HasPrefix(s, "64.0 GT/s"), strings.HasPrefix(s, "64 GT/s"):
+		return 6
+	}
+	return 0
+}
+
+func parsePCIe(out string) map[int]PCIeLink {
+	r := csv.NewReader(strings.NewReader(out))
+	r.TrimLeadingSpace = true
+	r.FieldsPerRecord = -1
+	rows, _ := r.ReadAll()
+	num := func(s string) int {
+		n, _ := strconv.Atoi(strings.TrimSpace(s))
+		return n
+	}
+	links := map[int]PCIeLink{}
+	for _, row := range rows {
+		if len(row) < 4 {
+			continue
+		}
+		idx, err := strconv.Atoi(strings.TrimSpace(row[0]))
+		if err != nil {
+			continue
+		}
+		l := PCIeLink{Gen: num(row[1]), Width: num(row[2]), WidthMax: num(row[3])}
+		if len(row) > 4 {
+			l.GPUGen = num(row[4])
+		}
+		links[idx] = l
+	}
+	return links
+}

internal/agent/discovery/pcie_test.go

@@ -0,0 +1,54 @@
+package discovery
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestACardInTheWrongSlotIsSaidSo(t *testing.T) {
+	for _, c := range []struct {
+		link PCIeLink
+		want string // empty: nothing to say
+	}{
+		// The PoC's Quadro RTX 6000, idle: current Gen1, but its fastest is 3,
+		// as the card's is, on all 16 lanes. Nothing wrong.
+		{PCIeLink{Gen: 3, GPUGen: 3, Width: 16, WidthMax: 16}, ""},
+		// An x16 card in a slot wired x8.
+		{PCIeLink{Gen: 4, GPUGen: 4, Width: 8, WidthMax: 16}, "x8 of its x16 lanes: 15.8 GB/s where it could have 31.5"},
+		// A Gen5 card in a Gen4 slot.
+		{PCIeLink{Gen: 4, GPUGen: 5, Width: 16, WidthMax: 16}, "PCIe Gen4 of its Gen5: 31.5 GB/s where it could have 63.0"},
+		// Both, behind a riser.
+		{PCIeLink{Gen: 3, GPUGen: 4, Width: 4, WidthMax: 16}, "x4 of its x16 lanes and PCIe Gen3 of its Gen4"},
+		// A driver that says nothing.
+		{PCIeLink{}, ""},
+	} {
+		got := c.link.Problem()
+		if (c.want == "") != (got == "") || !strings.Contains(got, c.want) {
+			t.Errorf("%+v: %q, want %q", c.link, got, c.want)
+		}
+	}
+}
+
+func TestTheLinkIsReadFromNvidiaSMI(t *testing.T) {
+	links := parsePCIe("0, 3, 16, 16, 3\n1, 4, 8, 16, [N/A]\n")
+	if links[0] != (PCIeLink{Gen: 3, GPUGen: 3, Width: 16, WidthMax: 16}) || links[1] != (PCIeLink{Gen: 4, Width: 8, WidthMax: 16}) {
+		t.Errorf("%+v", links)
+	}
+}
+
+func TestTheCardsOwnLanesComeFromTheKernel(t *testing.T) {
+	// The driver says x8 of x8 for a x16 card in a slot wired x8; the
+	// device's own max_link_width says 16.
+	root := t.TempDir()
+	dev := filepath.Join(root, "0000:3b:00.0")
+	_ = os.MkdirAll(dev, 0o755)
+	for f, v := range map[string]string{"max_link_width": "16", "current_link_width": "8", "max_link_speed": "16.0 GT/s PCIe"} {
+		_ = os.WriteFile(filepath.Join(dev, f), []byte(v+"\n"), 0o644)
+	}
+	l := withSysfs(PCIeLink{Gen: 4, Width: 8, WidthMax: 8}, root, "00000000:3B:00.0")
+	if l.WidthMax != 16 || l.Width != 8 || l.GPUGen != 4 || !strings.Contains(l.Problem(), "x8 of its x16") {
+		t.Errorf("%+v: %q", l, l.Problem())
+	}
+}

internal/agent/discovery/sensors.go

@@ -74,6 +74,13 @@ func NewSensorSampler() *SensorSampler {
 	return &SensorSampler{sys: "/sys", smi: runSMI, now: time.Now}
 }
 
+// SampleGPUs reads every card's heat, power and how busy it is now, without
+// a sampler's ten seconds of memory: for a screen that asks every few seconds
+// and wants what it asked for. Nil on a machine without nvidia-smi or a card.
+func SampleGPUs(ctx context.Context) []GPUSensor {
+	return (&SensorSampler{smi: runSMI}).gpus(ctx)
+}
+
 func runSMI(ctx context.Context, fields string) ([]byte, error) {
 	ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
 	defer cancel()

internal/agent/engines/engine.go

@@ -47,6 +47,13 @@ type Profile struct {
 	// KVEvents has the engine publish its KV cache events to the agent,
 	// for the router's precise index. vLLM only.
 	KVEvents bool `json:"kv_events,omitempty"`
+	// AllowPickle lets the node fetch weights in a pickle format, which run
+	// code when loaded; the catalog's allow_pickle.
+	AllowPickle bool `json:"allow_pickle,omitempty"`
+	// ModelSHA256 is the sha256 the registry published for the file
+	// ModelPath names; the node refuses a copy that is not it. Empty when
+	// nothing is known to check against.
+	ModelSHA256 string `json:"model_sha256,omitempty"`
 }
 
 // ShardSpec is one shard of one replica on this node.
@@ -215,6 +222,7 @@ func NewRegistry(cfg Config) *Registry {
 	r.Add(&TRTLLM{cfg: cfg.TRTLLM})
 	r.Add(&Sim{cfg: cfg.Sim})
 	r.Add(&ComfyUI{cfg: cfg.ComfyUI})
+	r.Add(&Strata{cfg: cfg.Strata})
 	return r
 }
 
@@ -265,6 +273,9 @@ type Config struct {
 	Sim    SimConfig    `koanf:"sim"`
 	// ComfyUI makes pictures; offered by a node whose ComfyUI is named here.
 	ComfyUI ComfyUIConfig `koanf:"comfyui"`
+	// Strata serves a few mixture-of-experts models from RAM and one card;
+	// offered by a node whose Strata is named here, or that installed it.
+	Strata StrataConfig `koanf:"strata"`
 }
 
 // --- shared helpers ---

internal/agent/engines/engines_test.go

@@ -477,14 +477,14 @@ func TestValidateRequiresModelPath(t *testing.T) {
 
 func TestRegistry(t *testing.T) {
 	r := NewRegistry(Config{})
-	if got := r.Names(); !slices.Equal(got, []string{"comfyui", "llamacpp", "sglang", "sim", "trtllm", "vllm"}) {
+	if got := r.Names(); !slices.Equal(got, []string{"comfyui", "llamacpp", "sglang", "sim", "strata", "trtllm", "vllm"}) {
 		t.Errorf("registry contents: %v", got)
 	}
 	if _, err := r.Get("vllm"); err != nil {
 		t.Errorf("vllm missing: %v", err)
 	}
 	err := func() error { _, err := r.Get("nope"); return err }()
-	if err == nil || !strings.Contains(err.Error(), "llamacpp, sglang, sim, trtllm, vllm") {
+	if err == nil || !strings.Contains(err.Error(), "llamacpp, sglang, sim, strata, trtllm, vllm") {
 		t.Errorf("an unknown engine should list what is available: %v", err)
 	}
 }

internal/agent/engines/pickle_test.go

@@ -0,0 +1,58 @@
+package engines
+
+import (
+	"slices"
+	"testing"
+)
+
+func TestAModelDownloadedByTheEngineIsReadAsSafetensorsOnly(t *testing.T) {
+	for path, want := range map[string]bool{
+		"Qwen/Qwen2.5-7B-Instruct":    true,
+		"/var/lib/llmgw/weights/abc/": false, "./local": false,
+		"http://m/q/v/": false, "q.gguf": false,
+	} {
+		got := slices.Contains(safetensorsOnly(Profile{ModelPath: path}), "safetensors")
+		if got != want {
+			t.Errorf("%q: safetensors only = %v, want %v", path, got, want)
+		}
+	}
+	if len(safetensorsOnly(Profile{ModelPath: "Qwen/Qwen2.5-7B-Instruct", AllowPickle: true})) != 0 {
+		t.Error("allow_pickle still forced safetensors")
+	}
+}
+
+func TestAForbiddenFlagIsKnownHoweverItIsSpelled(t *testing.T) {
+	for engine, args := range map[string][]string{
+		"vllm":   {"--trust_remote_code"},
+		"sglang": {"--load-format", "pt"},
+	} {
+		if UnsafeArgs(engine, args) == nil {
+			t.Errorf("%s %v was let through", engine, args)
+		}
+	}
+	for _, a := range [][]string{{"--load_format", "pt"}, {"--trust-remote"}, {"--load-form=pt"}} {
+		if UnsafeArgs("vllm", a) == nil {
+			t.Errorf("vllm %v was let through", a)
+		}
+	}
+	// What is not one of them, nor the start of one, still passes.
+	for _, a := range [][]string{{"--max-model-len", "8192"}, {"--tokenizer-mode", "mistral"}, {"--gpu-memory-utilization=0.9"}} {
+		if err := UnsafeArgs("vllm", a); err != nil {
+			t.Errorf("vllm %v was refused: %v", a, err)
+		}
+	}
+	// Short flags are matched as written; llama.cpp takes no abbreviations,
+	// so its --chat-template is not taken for --chat-template-file.
+	for _, a := range [][]string{{"-m", "x"}, {"-hf", "o/r"}, {"-mu", "http://x"}} {
+		if UnsafeArgs("llamacpp", a) == nil {
+			t.Errorf("llamacpp %v was let through", a)
+		}
+	}
+	if err := UnsafeArgs("llamacpp", []string{"--chat-template", "chatml"}); err != nil {
+		t.Errorf("llama.cpp's own --chat-template was refused: %v", err)
+	}
+	// ComfyUI's argparse reads --li as --listen.
+	if UnsafeArgs("comfyui", []string{"--li", "0.0.0.0"}) == nil {
+		t.Error("comfyui --li was let through")
+	}
+}

internal/agent/engines/sglang.go

@@ -102,6 +102,7 @@ func (g *SGLang) serverCommand(s ShardSpec) (Command, error) {
 	if p.ServedModelName != "" {
 		args = append(args, "--served-model-name", p.ServedModelName)
 	}
+	args = append(args, safetensorsOnly(p)...)
 	if s.NNodes > 1 {
 		args = append(args,
 			"--nnodes", strconv.Itoa(s.NNodes),

internal/agent/engines/strata.go

@@ -0,0 +1,184 @@
+package engines
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"sync/atomic"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/strata"
+)
+
+// StrataConfig locates a Strata installation.
+type StrataConfig struct {
+	// Dir is Strata's source directory, where setup.py and serve/ are.
+	Dir string `koanf:"dir"`
+	// Python is the interpreter of its environment; Dir's .venv when unset.
+	Python string `koanf:"python"`
+	// Engine is the directory of its prebuilt engine, where the strata
+	// binary and the CUDA libraries it ships are; Dir's engine/ when unset.
+	Engine string `koanf:"engine"`
+}
+
+// Strata runs Strata (github.com/Niko1221/Strata): a mixture-of-experts
+// engine that keeps a model's experts in RAM and the ones used most in VRAM,
+// so a 125B model serves from one 24 GB card. It runs a few model families
+// only, each prepared from its GGUF files by Strata's own setup, so the agent
+// starts llmgw strata-serve, which prepares the model and then becomes
+// Strata's server.
+type Strata struct {
+	cfg       StrataConfig
+	installed atomic.Pointer[string]
+}
+
+// Name identifies the engine in the catalog.
+func (*Strata) Name() string { return "strata" }
+
+// HealthPath answers 200 only once the model is loaded.
+func (*Strata) HealthPath() string { return "/health" }
+
+// MetricsPath is Strata's Prometheus text, in vLLM's names; its /metrics is
+// JSON for its own monitor unless asked for this format.
+func (*Strata) MetricsPath() string { return "/metrics?format=prometheus" }
+
+// ServesHTTP is true: a Strata replica is one process on one node.
+func (*Strata) ServesHTTP(ShardSpec) bool { return true }
+
+// UseInstalled points the engine at the environment the agent installed:
+// its interpreter, with Strata's code beside its bin in strata/ and the
+// engine in strata-engine/.
+func (s *Strata) UseInstalled(python string) { s.installed.Store(&python) }
+
+// Configured reports whether the configuration names a Strata.
+func (s *Strata) Configured() bool { return s.cfg.Dir != "" }
+
+// StrataSourceDir and StrataEngineDir are where an installed environment
+// keeps Strata's code and its prebuilt engine, beside bin/.
+const (
+	StrataSourceDir = "strata"
+	StrataEngineDir = "strata-engine"
+)
+
+func (s *Strata) env() string {
+	if p := s.installed.Load(); p != nil {
+		return filepath.Dir(filepath.Dir(*p))
+	}
+	return ""
+}
+
+func (s *Strata) dir() string {
+	if e := s.env(); e != "" {
+		return filepath.Join(e, StrataSourceDir)
+	}
+	return s.cfg.Dir
+}
+
+func (s *Strata) engineDir() string {
+	if e := s.env(); e != "" {
+		return filepath.Join(e, StrataEngineDir)
+	}
+	if s.cfg.Engine != "" {
+		return s.cfg.Engine
+	}
+	return filepath.Join(s.cfg.Dir, "engine")
+}
+
+func (s *Strata) python() string {
+	if p := s.installed.Load(); p != nil {
+		return *p
+	}
+	if s.cfg.Python != "" {
+		return s.cfg.Python
+	}
+	return filepath.Join(s.cfg.Dir, ".venv", "bin", "python")
+}
+
+var strataVersion = regexp.MustCompile(`PRODUCT_VERSION\s*=\s*"([^"]+)"`)
+
+// Probe reports the Strata a configuration names, by the version its source
+// states: a directory with its setup and server, an interpreter, and the
+// engine binary. Without it a Strata named by hand was never reported, and
+// so never placed on.
+func (s *Strata) Probe(context.Context) (string, error) {
+	dir := s.dir()
+	if dir == "" {
+		return "", fmt.Errorf("no Strata directory is configured")
+	}
+	for _, f := range []string{filepath.Join(dir, "setup.py"), filepath.Join(dir, "serve", "server.py"),
+		s.python(), filepath.Join(s.engineDir(), "strata")} {
+		if _, err := os.Stat(f); err != nil {
+			return "", fmt.Errorf("%s is not a whole Strata: %w", dir, err)
+		}
+	}
+	b, err := os.ReadFile(filepath.Join(dir, "strata_cli", "__init__.py"))
+	if err != nil {
+		return Unknown, nil //nolint:nilerr // whole, of a version it does not say
+	}
+	if m := strataVersion.FindSubmatch(b); m != nil {
+		return string(m[1]), nil
+	}
+	return Unknown, nil
+}
+
+// Validate checks the profile: one card, on one node. Strata splits a model
+// over a node's cards by layer, but that is not driven from here yet.
+func (*Strata) Validate(p Profile, gpus []GPUInfo) error {
+	if p.Nodes > 1 || p.TP > 1 || p.PP > 1 || p.GPUsPerNode > 1 {
+		return fmt.Errorf("profile %q: strata runs on one GPU of one node", p.Name)
+	}
+	// Pascal and Volta run its CUDA 12 build, which the install picks for
+	// them.
+	if err := requireComputeCapability(p, gpus, 6.0, "strata"); err != nil {
+		return err
+	}
+	// A family whose engine needs more: said now, rather than by Strata's
+	// setup after the replica was placed here.
+	if fam, ok := strata.FamilyNamed(strata.ArgValue(p.Args, "--family")); ok && fam.MinCC > 0 {
+		if err := requireComputeCapability(p, gpus, fam.MinCC, "strata's "+fam.Title+" engine"); err != nil {
+			return err
+		}
+	}
+	return validateCommon(p, gpus)
+}
+
+// Commands is llmgw strata-serve, which prepares the model with Strata's
+// setup and then execs Strata's server.
+func (s *Strata) Commands(sh ShardSpec) ([]Command, error) {
+	dir := s.dir()
+	if dir == "" {
+		return nil, fmt.Errorf("strata: no Strata directory is configured (engines.strata.dir)")
+	}
+	bin, err := os.Executable()
+	if err != nil {
+		return nil, err
+	}
+	p := sh.Profile
+	args := []string{"strata-serve",
+		"--listen", net.JoinHostPort(sh.Host(), strconv.Itoa(sh.HTTPPort)),
+		"--model", p.ServedModelName,
+		"--weights", p.ModelPath,
+		// Relative to where engines run — their user's home — so they are
+		// theirs to write. The data is shared by the node's replicas: a
+		// prepared model and its draft layer are gigabytes, the same for
+		// every replica of it.
+		"--state", filepath.Join("strata", sh.ReplicaID),
+		"--data", filepath.Join("strata", "data"),
+		"--python", s.python(),
+		"--strata", dir,
+		"--engine", s.engineDir(),
+		"--",
+	}
+	args = append(args, p.Args...)
+	env := baseEnv(sh)
+	if sh.APIKey != "" {
+		// Strata's server reads its key from here, and strata-serve passes
+		// it on in the environment: not on a command line every user on the
+		// node can read.
+		env["STRATA_API_KEY"] = sh.APIKey
+	}
+	return []Command{{Name: "strata", Path: bin, Args: args, Env: materializeEnv(env)}}, nil
+}

internal/agent/engines/strata_test.go

@@ -0,0 +1,113 @@
+package engines
+
+import (
+	"os"
+	"path/filepath"
+	"slices"
+	"strings"
+	"testing"
+)
+
+func TestStrataStartsStrataServeWithTheKeyInTheEnvironment(t *testing.T) {
+	s := &Strata{}
+	s.UseInstalled("/opt/llmgw/engines/strata/0.2.7-cuda13/bin/python")
+	spec := ShardSpec{
+		ReplicaID: "r1", HTTPPort: 18090, BindAddr: "10.0.0.147", GPUIndices: []int{0},
+		APIKey: "secret-key",
+		Profile: Profile{Name: "p", Engine: "strata", TP: 1, ModelPath: "/var/lib/llmgw/models/q38",
+			ServedModelName: "qwen3.8-flash-next", Args: []string{"--family", "qwen", "--size", "IQ2_XS"}},
+	}
+	cmds, err := s.Commands(spec)
+	if err != nil {
+		t.Fatal(err)
+	}
+	c := cmds[0]
+	args := strings.Join(c.Args, " ")
+	env := "/opt/llmgw/engines/strata/0.2.7-cuda13"
+	for _, want := range []string{
+		"strata-serve", "--listen 10.0.0.147:18090", "--model qwen3.8-flash-next",
+		"--weights /var/lib/llmgw/models/q38", "--state " + filepath.Join("strata", "r1"),
+		"--python " + env + "/bin/python", "--strata " + env + "/strata", "--engine " + env + "/strata-engine",
+		"-- --family qwen --size IQ2_XS",
+	} {
+		if !strings.Contains(args, want) {
+			t.Errorf("args lack %q: %s", want, args)
+		}
+	}
+	if strings.Contains(args, "secret-key") {
+		t.Error("the key is on the command line, which every user on the node can read")
+	}
+	if !slices.Contains(c.Env, "STRATA_API_KEY=secret-key") {
+		t.Error("the key is not in the environment, where Strata's server reads it")
+	}
+	if !slices.Contains(c.Env, "CUDA_VISIBLE_DEVICES=0") {
+		t.Error("the shard is not pinned to its GPU")
+	}
+}
+
+func TestStrataRunsOnOneCard(t *testing.T) {
+	s := &Strata{}
+	p := Profile{Name: "p", Engine: "strata", TP: 1, GPUsPerNode: 2, ModelPath: "/m"}
+	if err := s.Validate(p, nil); err == nil {
+		t.Error("a two-card profile was accepted")
+	}
+	p.GPUsPerNode = 1
+	if err := s.Validate(p, []GPUInfo{{Name: "Quadro RTX 6000", ComputeCapability: "7.5"}}); err != nil {
+		t.Errorf("one Turing card was refused: %v", err)
+	}
+}
+
+func TestStrataSetupFlagsThatMoveFilesAreRefused(t *testing.T) {
+	for _, bad := range []string{"--gguf-dir", "--gguf", "--data-dir=/etc", "--model", "--mod", "--feed", "--host", "--gpus"} {
+		if err := UnsafeArgs("strata", []string{bad, "x"}); err == nil {
+			t.Errorf("%s was accepted", bad)
+		}
+	}
+	if err := UnsafeArgs("strata", []string{"--family", "qwen", "--size", "IQ2_XS", "--context", "32768",
+		"--parallel", "2", "--vram-reserve-mib", "2048", "--vision", "no"}); err != nil {
+		t.Errorf("an ordinary profile was refused: %v", err)
+	}
+}
+
+func TestAStrataNamedByHandIsReportedWithItsVersion(t *testing.T) {
+	dir := t.TempDir()
+	for _, f := range []string{"setup.py", "serve/server.py", ".venv/bin/python", "engine/strata"} {
+		p := filepath.Join(dir, f)
+		if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(p, nil, 0o755); err != nil {
+			t.Fatal(err)
+		}
+	}
+	s := &Strata{cfg: StrataConfig{Dir: dir}}
+	if v, err := s.Probe(t.Context()); err != nil || v != Unknown {
+		t.Fatalf("%q %v", v, err)
+	}
+	_ = os.MkdirAll(filepath.Join(dir, "strata_cli"), 0o755)
+	_ = os.WriteFile(filepath.Join(dir, "strata_cli", "__init__.py"), []byte("PRODUCT_VERSION = \"0.2.7\"\n"), 0o644)
+	if v, _ := s.Probe(t.Context()); v != "0.2.7" {
+		t.Errorf("version %q", v)
+	}
+	r := NewRegistry(Config{Strata: StrataConfig{Dir: dir}})
+	if got := r.ProbeConfigured(t.Context()); got["strata"] != "0.2.7" {
+		t.Errorf("not reported: %v", got)
+	}
+	_ = os.Remove(filepath.Join(dir, "engine", "strata"))
+	if _, err := s.Probe(t.Context()); err == nil {
+		t.Error("reported without its engine")
+	}
+}
+
+func TestStrataRefusesDeepSeekOnACardItsEngineWasNotBuiltFor(t *testing.T) {
+	s := &Strata{}
+	p := Profile{Name: "p", Engine: "strata", ModelPath: "/m", TP: 1, GPUsPerNode: 1, Args: []string{"--family", "deepseek41", "--size", "IST-DAS-1.75bpw"}}
+	gpus := []GPUInfo{{Index: 0, Name: "Quadro RTX 6000", ComputeCapability: "7.5"}}
+	if err := s.Validate(p, gpus); err == nil || !strings.Contains(err.Error(), "8.6") {
+		t.Errorf("DeepSeek on 7.5: %v", err)
+	}
+	p.Args = []string{"--family", "qwen", "--size", "IQ2_XS"}
+	if err := s.Validate(p, gpus); err != nil {
+		t.Errorf("Qwen on 7.5: %v", err)
+	}
+}

internal/agent/engines/unsafeenv.go

@@ -2,6 +2,7 @@ package engines
 
 import (
 	"fmt"
+	"os"
 	"strings"
 )
 
@@ -101,6 +102,13 @@ var flagsNever = map[string]map[string]string{
 		"--hf-token": "is a credential", "--alias": "is set by the agent",
 		"--model-draft": "loads a file", "-md": "loads a file",
 		"--prompt-cache": "writes a file", "--logdir": "writes files",
+		// The short spellings of the same.
+		"-mm": "loads a file; the projector is fetched with the model", "--mmproj-url": "downloads a file",
+		"-mmu": "downloads a file", "-hfr": "downloads a model", "-hff": "downloads a model",
+		"--hf-repo-draft": "downloads a model", "-hfd": "downloads a model", "-hfrd": "downloads a model",
+		"--hf-repo-v": "downloads a model", "-hfv": "downloads a model", "--hf-file-v": "downloads a model",
+		"-hffv": "downloads a model", "-hft": "is a credential", "-jf": "reads a file", "-a": "is set by the agent",
+		"--model-vocoder": "loads a file", "-mv": "loads a file",
 	},
 	"vllm": {
 		"--download-dir": "writes files", "--tokenizer": "reads another repository or path",
@@ -118,6 +126,7 @@ var flagsNever = map[string]map[string]string{
 		"--file-storage-path": "writes files", "--log-requests": "logs prompts",
 		"--model-path": "is the model's source, set by the agent", "--served-model-name": "is set by the agent",
 		"--lora-paths": "loads files", "--download-dir": "writes files",
+		"--load-format": "changes how weights are loaded, some ways running code",
 	},
 	// ComfyUI's main.py, behind the gate that sets where it listens and
 	// where its files are.
@@ -132,6 +141,22 @@ var flagsNever = map[string]map[string]string{
 		"--tls-keyfile":        "reads a file", "--tls-certfile": "reads a file",
 		"--comfy-api-base": "sends work to another service",
 	},
+	// Strata's setup.py, which a profile's arguments go to: llmgw
+	// strata-serve sets where the model is, where its files go and where
+	// the server listens, and the engine is the one the agent installed.
+	// Its own --model, the size, is spelt --size in a profile, since
+	// --model is the source everywhere else.
+	"strata": {
+		"--gguf-dir": "is the model's source, set by the agent", "--models-dir": "is set by the agent",
+		"--data-dir": "is set by the agent", "--move-data": "moves files", "--set-default-data-dir": "writes settings",
+		"--feed": "downloads an engine", "--prebuilt": "loads an engine", "--build": "compiles an engine",
+		"--update": "downloads an engine", "--rollback-engine": "changes the engine",
+		"--dsv41-package": "loads a file", "--inspect": "reads another repository or path",
+		"--source": "downloads from elsewhere", "--setup": "is not for a server",
+		"--browser": "opens a browser", "--gpu": "is set by the agent", "--gpus": "is set by the agent",
+		"--gpu-roles": "is set by the agent", "--backend": "is set by the agent",
+		"--experimental-speed-projection": "changes what the model refuses",
+	},
 	// trtllm-serve spells its flags with underscores, so the shared list's
 	// hyphenated names do not reach them.
 	"trtllm": {
@@ -163,14 +188,43 @@ var flagsNever = map[string]map[string]string{
 // unsafeFlag is why an engine may not be given a flag, or "".
 func unsafeFlag(engine, flag, _ string) string {
 	name, _, _ := strings.Cut(flag, "=")
+	if !strings.HasPrefix(name, "-") {
+		return ""
+	}
+	// Written as the engine would read it: vLLM takes --load_format for
+	// --load-format, TensorRT-LLM the other way round. Short flags (-m,
+	// -hf) are matched as written.
+	norm := func(f string) string {
+		if strings.HasPrefix(f, "--") {
+			return "--" + strings.ReplaceAll(f[2:], "_", "-")
+		}
+		return f
+	}
+	given := norm(name)
+	// argparse also takes any unambiguous beginning of a long flag for the
+	// flag — --trust-remote is --trust-remote-code, --li is ComfyUI's
+	// --listen — so for the engines that parse with it, a beginning of a
+	// refused flag is refused. llama.cpp and TensorRT-LLM take no such
+	// thing, and --chat-template there is a flag of its own.
+	abbreviates := argparseEngines[engine] && strings.HasPrefix(given, "--") && len(given) >= 4
 	for _, set := range []string{"", engine} {
-		if why, ok := flagsNever[set][name]; ok && why != "" {
-			return why
+		for never, why := range flagsNever[set] {
+			if why == "" {
+				continue
+			}
+			n := norm(never)
+			if n == given || (abbreviates && strings.HasPrefix(n, "--") && strings.HasPrefix(n, given)) {
+				return why
+			}
 		}
 	}
 	return ""
 }
 
+// argparseEngines read their flags with Python's argparse, which takes a
+// long flag's beginning for the flag.
+var argparseEngines = map[string]bool{"vllm": true, "sglang": true, "comfyui": true, "strata": true}
+
 // UnsafeArgs refuses the first of a profile's arguments an engine may not be
 // given, saying why.
 func UnsafeArgs(engine string, args []string) error {
@@ -185,3 +239,29 @@ func UnsafeArgs(engine string, args []string) error {
 	}
 	return nil
 }
+
+// safetensorsOnly has vLLM or SGLang read only safetensors from a model it
+// downloads itself, by its Hugging Face id: left to choose, either takes
+// the repository's pickle files (pytorch_model.bin) when it has no
+// safetensors, and loading those runs whatever they hold. A path was
+// fetched by the agent, which checked it, or put there by the operator.
+func safetensorsOnly(p Profile) []string {
+	if p.AllowPickle || !hubID(p.ModelPath) {
+		return nil
+	}
+	return []string{"--load-format", "safetensors"}
+}
+
+// hubID reports whether a model path is a Hugging Face id, org/name, rather
+// than a file or directory.
+func hubID(s string) bool {
+	if s == "" || strings.HasPrefix(s, "/") || strings.HasPrefix(s, ".") || strings.Contains(s, "://") {
+		return false
+	}
+	// org/name:Q4_K_M is a GGUF in a repository, which vLLM reads as one.
+	if strings.Count(s, "/") != 1 || strings.Contains(s, ":") {
+		return false
+	}
+	_, err := os.Stat(s)
+	return err != nil
+}

internal/agent/engines/vllm.go

@@ -119,6 +119,7 @@ func (v *VLLM) serverCommand(s ShardSpec) (Command, error) {
 	if p.ServedModelName != "" {
 		args = append(args, "--served-model-name", p.ServedModelName)
 	}
+	args = append(args, safetensorsOnly(p)...)
 
 	env := baseEnv(s)
 

internal/agent/gpucheck.go

@@ -20,6 +20,7 @@ var (
 	gpuProcesses = discovery.GPUProcesses
 	gpuMemory    = discovery.GPUMemoryByProcess
 	processGroup = pgidOf
+	parentOf     = ppidOf
 	// gpuCheckWait is how long a shard has, once it answers, to show up on
 	// its GPUs: the weights are on them by then, but nvidia-smi can lag.
 	gpuCheckWait = 15 * time.Second
@@ -116,19 +117,44 @@ func (a *Agent) foreignGPUMemory(ctx context.Context, shards []int) (foreign, us
 	return foreign, used
 }
 
-// holds reports whether any of pids is the shard's process or in its group:
-// an engine that computes in a child process is still the shard.
+// holds reports whether any of pids is the shard's process, in its group,
+// or a process it started: an engine that computes in a child process is
+// still the shard, and Strata's server starts its engine in a group of the
+// engine's own.
 func holds(pids []int, pid, group int) bool {
 	for _, p := range pids {
-		if p == pid || (group > 0 && processGroup(p) == group) {
+		if p == pid || (group > 0 && processGroup(p) == group) || descends(p, pid) {
 			return true
 		}
 	}
 	return false
 }
 
+// descends reports whether process p was started, at any remove, by pid.
+func descends(p, pid int) bool {
+	// Bounded: a chain this deep is no engine's, and a /proc read racing an
+	// exit must not loop.
+	for range 16 {
+		p = parentOf(p)
+		switch {
+		case p == pid:
+			return true
+		case p <= 1:
+			return false
+		}
+	}
+	return false
+}
+
 // pgidOf reads a process's group from /proc; zero when it cannot.
-func pgidOf(pid int) int {
+func pgidOf(pid int) int { return statField(pid, 2) }
+
+// ppidOf reads a process's parent from /proc; zero when it cannot.
+func ppidOf(pid int) int { return statField(pid, 1) }
+
+// statField is one of the numbers after the command name in /proc's stat
+// line: 1 is the parent, 2 the group.
+func statField(pid, field int) int {
 	b, err := os.ReadFile("/proc/" + strconv.Itoa(pid) + "/stat")
 	if err != nil {
 		return 0
@@ -141,10 +167,10 @@ func pgidOf(pid int) int {
 		return 0
 	}
 	f := strings.Fields(s[i+1:])
-	if len(f) < 3 {
+	if len(f) <= field {
 		return 0
 	}
-	n, _ := strconv.Atoi(f[2])
+	n, _ := strconv.Atoi(f[field])
 	return n
 }
 

internal/agent/gpucheck_test.go

@@ -123,6 +123,30 @@ func TestForeignGPUMemoryLeavesOutTheAgentsOwnShards(t *testing.T) {
 	}
 }
 
+func TestAnEngineStartedInAGroupOfItsOwnIsStillTheShards(t *testing.T) {
+	// cuda01: Strata's server (259709) starts its engine (261072) in a
+	// group of the engine's own, and the engine holds the card. It read as
+	// a shard on the CPU, and as 22 GB of somebody else's memory.
+	oldMem, oldGroup, oldParent := gpuMemory, processGroup, parentOf
+	t.Cleanup(func() { gpuMemory, processGroup, parentOf = oldMem, oldGroup, oldParent })
+	processGroup = func(pid int) int { return pid }
+	parentOf = func(pid int) int {
+		return map[int]int{261072: 259709, 259709: 258734, 258734: 1, 999: 1}[pid]
+	}
+	gpuMemory = func(context.Context, string) ([]discovery.GPUMemory, error) {
+		return []discovery.GPUMemory{{Index: 0, UsedMB: 23000,
+			Procs: []discovery.GPUProcess{{PID: 261072, UsedMB: 22226}, {PID: 999, UsedMB: 700}}}}, nil
+	}
+	a := &Agent{log: slog.Default()}
+	if c, ok := a.gpuCompute(context.Background(), []int{0}, 259709); !ok || c.Backend != "CUDA" ||
+		len(c.Devices) != 1 || c.Devices[0] != "GPU 0: 21.7 GB" {
+		t.Errorf("the engine's child on GPU 0: %+v %v", c, ok)
+	}
+	if foreign, _ := a.foreignGPUMemory(context.Background(), []int{259709}); !slices.Equal(foreign, []int32{774}) {
+		t.Errorf("foreign %v; want only what the other process and nobody holds, [774]", foreign)
+	}
+}
+
 func TestLlamaCppsOwnWordOnTheCPUIsEnoughToRefuse(t *testing.T) {
 	eng := fallbackEngine{}
 	// Without nvidia-smi to ask, the engine's own output says it.

internal/agent/main_test.go

@@ -0,0 +1,15 @@
+package agent
+
+import (
+	"os"
+	"testing"
+	"time"
+)
+
+func TestMain(m *testing.M) {
+	// Half a gigabyte read per test binary, and contending with the tests
+	// for the CPUs: these never look at the figure.
+	measureBandwidth = func() float64 { return 0 }
+	bandwidthDelay = func() time.Duration { return 0 }
+	os.Exit(m.Run())
+}

internal/agent/provision/install.go

@@ -174,7 +174,7 @@ func (in *Installer) one(ctx context.Context, w Want) Status {
 		}
 		return st
 	}
-	if w.Offline != nil && recipe.Repo == "" {
+	if w.Offline != nil && (recipe.Repo == "" || builds[0].Python != "") {
 		// Said, not attempted: uv would spend minutes failing to reach PyPI,
 		// and the failure would read like a network fault rather than the
 		// design of an offline site.

internal/agent/provision/python.go

@@ -109,6 +109,11 @@ func (in *Installer) installPython(ctx context.Context, r Recipe, w Want, b Buil
 		}
 		reqs = append(reqs, more...)
 	}
+	if len(b.Assets) > 0 {
+		if err := in.unpackAssets(ctx, r, w, b, tmp, st); err != nil {
+			return err
+		}
+	}
 	if b.Wheel != nil {
 		// The engine from its GitHub release, pinned to the digest GitHub
 		// publishes for the file: the same trust as an archive, and uv
@@ -372,6 +377,48 @@ func (in *Installer) unpackSource(ctx context.Context, w Want, b Build, env stri
 	return requirementsIn(string(f), b.IndexPackages)
 }
 
+// unpackAssets fetches a Python engine's release binaries, each checked
+// against the digest GitHub publishes for it, and unpacks them into the
+// environment's AssetDir.
+func (in *Installer) unpackAssets(ctx context.Context, r Recipe, w Want, b Build, env string, st *Status) error {
+	tag := b.AssetTag
+	if tag == "" {
+		tag = w.Version
+	}
+	in.progress(st, "asking GitHub for the checksums of %s %s", r.Repo, tag)
+	sums, err := in.checksums(ctx, r.Repo, tag)
+	if err != nil {
+		return err
+	}
+	dst := filepath.Join(env, b.AssetDir)
+	if err := os.MkdirAll(dst, 0o755); err != nil {
+		return err
+	}
+	for _, asset := range b.Assets {
+		want, ok := sums[asset]
+		if !ok {
+			// Refused rather than installed unchecked: this is a binary that
+			// will run on every node.
+			return fmt.Errorf("%s %s publishes no checksum for %s, so it cannot be verified", r.Repo, tag, asset)
+		}
+		url := strings.TrimSuffix(in.downloadBase(), "/") + "/" + r.Repo + "/releases/download/" + tag + "/" + asset
+		archive := filepath.Join(env+".source", asset)
+		if err := os.MkdirAll(filepath.Dir(archive), 0o755); err != nil {
+			return err
+		}
+		if err := in.download(ctx, url, asset, archive, want, st); err != nil {
+			return err
+		}
+		in.progress(st, "unpacking %s", asset)
+		err := untarGz(archive, dst)
+		_ = os.RemoveAll(filepath.Dir(archive))
+		if err != nil {
+			return fmt.Errorf("unpacking %s: %w", asset, err)
+		}
+	}
+	return nil
+}
+
 // requirementsIn reads a requirements file's lines. Options (-r, -e, --index-url
 // and the like) are refused: they would fetch from somewhere other than PyPI,
 // or install what the lock never saw.

internal/agent/provision/recipe.go

@@ -76,6 +76,11 @@ type Build struct {
 	// was published, which PyPI cannot be asked for.
 	Source *Source
 	AsOf   time.Time
+	// AssetTag and AssetDir, for a Python engine that also ships a binary
+	// in its releases, are the release tag Assets are taken from, checked
+	// against the digests GitHub publishes, and the directory in the
+	// environment they are unpacked into.
+	AssetTag, AssetDir string
 	// FreeGB is the disk space the installation needs before it starts: a
 	// Python engine is several gigabytes, and one that fills the disk halfway
 	// leaves the node worse off than one that never began.
@@ -125,6 +130,7 @@ var Recipes = map[string]Recipe{
 	"vllm":     {PyPI: "vllm", Candidates: vllmCandidates},
 	"sglang":   {PyPI: "sglang", Candidates: sglangCandidates},
 	"comfyui":  {Candidates: comfyuiCandidates},
+	"strata":   {Repo: StrataRepo, Candidates: strataCandidates},
 	"uv":       {Repo: "astral-sh/uv", Candidates: uvCandidates},
 }
 
@@ -172,6 +178,9 @@ func Builds(engine, version, arch string) ([]Build, error) {
 			continue
 		}
 		for _, b := range bs {
+			if b.Python != "" {
+				return nil, fmt.Errorf("%s is a Python environment from PyPI, which an offline bundle does not carry", engine)
+			}
 			if !seen[b.Variant] {
 				seen[b.Variant] = true
 				out = append(out, b)
@@ -672,3 +681,80 @@ print("comfyui version", "` + version + `", "on torch", torch.__version__)`},
 		{cu126, gpuNeeds{minDriverForCUDA12, 5.0}, "ComfyUI " + version + " on CUDA 12.6's torch"},
 	}, h)
 }
+
+// --- Strata ---
+
+// StrataRepo is where Strata is published: its source, and in each release
+// the prebuilt engine for each CUDA.
+const StrataRepo = "Niko1221/Strata"
+
+// strataReleases are the Strata versions this agent installs: the source
+// archive's digest, taken when it was added here and confirmed from a second
+// machine, when the version was published, and the engine its release
+// carries, whose files GitHub publishes digests for.
+var strataReleases = map[string]struct {
+	sha256    string
+	published string
+	engine    string
+}{
+	"0.2.7": {"41ae861478f5e5d9506864f97dfb5dd7cfe6b83193300e2b0d4f04c0380e3af9", "2026-10-27T14:54:42Z", "0.1.52"},
+}
+
+// strataCandidates are the Strata builds for a machine: its source, in a
+// Python environment, with the prebuilt engine for the node's driver and
+// cards — built for CUDA 13, Turing to Blackwell; or for CUDA 12.9, Pascal
+// to Ada, which is what a V100, or a driver older than 580, gets.
+func strataCandidates(version, variant string, h discovery.Host) ([]Build, error) {
+	if _, err := gpuArch("Strata", h); err != nil {
+		return nil, err
+	}
+	if h.Arch != "amd64" {
+		return nil, NotHere{"Strata publishes its Linux CUDA engine for x86-64 only"}
+	}
+	rel, ok := strataReleases[version]
+	if !ok {
+		known := make([]string, 0, len(strataReleases))
+		for v := range strataReleases {
+			known = append(known, v)
+		}
+		slices.Sort(known)
+		return nil, fmt.Errorf("this agent knows the source digest of Strata %s, not of %s; "+
+			"install that one by hand and name it in agent.yaml (engines.strata.dir)",
+			strings.Join(known, ", "), version)
+	}
+	published, err := time.Parse(time.RFC3339, rel.published)
+	if err != nil {
+		return nil, err
+	}
+	build := func(cuda string) Build {
+		return Build{
+			Variant: cuda,
+			Python:  pythonForEngines,
+			Source: &Source{
+				URL:    "/" + StrataRepo + "/archive/refs/tags/v" + version + ".tar.gz",
+				SHA256: rel.sha256, Top: "Strata-" + version, Dir: "strata",
+				Requirements: "requirements.txt",
+			},
+			AsOf:     published.Add(24 * time.Hour),
+			Assets:   []string{"strata-engine-" + rel.engine + "-linux-x86_64-cuda-" + cuda + ".tar.gz"},
+			AssetTag: "v" + version,
+			AssetDir: "strata-engine",
+			// Strata is started as a script, so what the agent is given is
+			// the environment's interpreter; the proof is importing what its
+			// server needs, and finding its engine beside it.
+			Binary: "python",
+			VersionArgs: []string{"-c", `import os, sys, numpy, jinja2, regex
+e = os.path.dirname(os.path.dirname(os.path.abspath(sys.executable)))
+for f in ("strata/setup.py", "strata/serve/server.py", "strata-engine/strata"):
+    assert os.path.isfile(os.path.join(e, f)), f + " is missing"
+print("strata version", "` + version + `", "engine", "` + rel.engine + `")`},
+			FreeGB: 5,
+		}
+	}
+	return pick("Strata "+version, variant, []candidate{
+		{build("cuda13"), gpuNeeds{minDriverForCUDA13, 7.5}, "Strata " + version + " built for CUDA 13"},
+		// 12.9 rather than 12: its machine code is for 6.0 to 8.9 and its
+		// PTX was compiled by 12.9, so the driver must be 575.
+		{build("cuda12"), gpuNeeds{575, 6.0}, "Strata " + version + " built for CUDA 12.9"},
+	}, h)
+}

internal/agent/provision/strata_test.go

@@ -0,0 +1,118 @@
+package provision
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/agent/discovery"
+)
+
+// strataRelease is Strata's source archive as GitHub makes one, and its
+// release's engine for CUDA 13, with the recipe pointed at the archive.
+func strataRelease(t *testing.T, rel *release) {
+	t.Helper()
+	archive := tarGz(t, map[string]string{
+		"Strata-0.2.7/setup.py":         "print('setup')\n",
+		"Strata-0.2.7/serve/server.py":  "print('server')\n",
+		"Strata-0.2.7/requirements.txt": "numpy==2.5.3; python_version >= \"3.12\"\njinja2==3.1.6\n",
+	}, nil)
+	rel.assets["v0.2.7.tar.gz"] = archive
+	sum := sha256.Sum256(archive)
+	engine := tarGz(t, map[string]string{"strata": "\x7fELF", "libcudart.so.13": "lib"}, nil)
+	name := "strata-engine-0.1.52-linux-x86_64-cuda-cuda13.tar.gz"
+	rel.assets[name] = engine
+	esum := sha256.Sum256(engine)
+	rel.digests[name] = "sha256:" + hex.EncodeToString(esum[:])
+
+	old := strataReleases
+	strataReleases = map[string]struct {
+		sha256    string
+		published string
+		engine    string
+	}{"0.2.7": {hex.EncodeToString(sum[:]), "2026-10-27T14:54:42Z", "0.1.52"}}
+	t.Cleanup(func() { strataReleases = old })
+}
+
+func TestStrataIsInstalledWithItsEngineBesideItsCode(t *testing.T) {
+	sys := &fakePython{fakeSystem: fakeSystem{installed: map[string]bool{}}}
+	in, rel := pythonInstaller(t, turingNode, sys)
+	strataRelease(t, rel)
+
+	got := in.Converge(t.Context(), []Want{{Engine: "strata", Version: "0.2.7"}})
+	if got[0].State != Ready {
+		t.Fatalf("not ready: %+v", got[0])
+	}
+	dir := filepath.Join(in.Root, "strata", "0.2.7-cuda13")
+	if got[0].Binary != filepath.Join(dir, "bin", "python") {
+		t.Errorf("binary %s, want the environment's interpreter", got[0].Binary)
+	}
+	for _, f := range []string{"strata/setup.py", "strata/serve/server.py", "strata-engine/strata", "strata-engine/libcudart.so.13"} {
+		if _, err := os.Stat(filepath.Join(dir, f)); err != nil {
+			t.Errorf("%s is not in the environment: %v", f, err)
+		}
+	}
+	all := strings.Join(sys.commands, "\n")
+	for _, want := range []string{"--exclude-newer 2026-10-28T14:54:42Z", "jinja2==3.1.6"} {
+		if !strings.Contains(all, want) {
+			t.Errorf("the installation never used %q:\n%s", want, all)
+		}
+	}
+}
+
+func TestStrataRefusesAnEngineWhoseDigestDoesNotMatch(t *testing.T) {
+	sys := &fakePython{fakeSystem: fakeSystem{installed: map[string]bool{}}}
+	in, rel := pythonInstaller(t, turingNode, sys)
+	strataRelease(t, rel)
+	rel.digests["strata-engine-0.1.52-linux-x86_64-cuda-cuda13.tar.gz"] = "sha256:" + strings.Repeat("0", 64)
+
+	got := in.Converge(t.Context(), []Want{{Engine: "strata", Version: "0.2.7", Variant: "cuda13"}})
+	if got[0].State != Failed || !strings.Contains(got[0].Detail, "does not match the checksum") {
+		t.Fatalf("an engine that does not match its digest was not refused: %+v", got[0])
+	}
+}
+
+func TestStrataPicksTheEngineForTheCardsAndDriver(t *testing.T) {
+	for _, tc := range []struct {
+		name string
+		host discovery.Host
+		want []string
+		err  string
+	}{
+		{"turing on 580", turingNode, []string{"cuda13", "cuda12"}, ""},
+		{"volta", discovery.Host{Arch: "amd64", NVIDIADriver: "580.82.07", MinComputeCapability: 7.0}, []string{"cuda12"}, ""},
+		{"driver 575", discovery.Host{Arch: "amd64", NVIDIADriver: "575.51.03", MinComputeCapability: 8.6}, []string{"cuda12"}, ""},
+		{"driver 570", discovery.Host{Arch: "amd64", NVIDIADriver: "570.86.10", MinComputeCapability: 8.6}, nil, "575"},
+		{"no gpu", discovery.Host{Arch: "amd64"}, nil, "no"},
+		{"arm", discovery.Host{Arch: "arm64", NVIDIADriver: "580.82.07", MinComputeCapability: 9.0}, nil, "x86-64"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			bs, err := strataCandidates("0.2.7", "", tc.host)
+			if tc.err != "" {
+				if err == nil || !strings.Contains(err.Error(), tc.err) {
+					t.Fatalf("got %v, %v; want an error saying %q", bs, err, tc.err)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatal(err)
+			}
+			var got []string
+			for _, b := range bs {
+				got = append(got, b.Variant)
+			}
+			if strings.Join(got, ",") != strings.Join(tc.want, ",") {
+				t.Errorf("builds %v, want %v", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestStrataIsNotInAnOfflineBundle(t *testing.T) {
+	if _, err := Builds("strata", "0.2.7", "amd64"); err == nil {
+		t.Fatal("an offline bundle would carry Strata, which needs PyPI")
+	}
+}

internal/agent/supervisor/process_unix.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"os"
 	"strconv"
+	"strings"
 	"syscall"
 )
 
@@ -63,3 +64,71 @@ func isZombie(pid int) bool {
 	}
 	return b[i+2] == 'Z'
 }
+
+// strays are a process's descendants that left its group, as an engine that
+// starts its worker in a session of its own does (Strata): signalling the
+// group misses them, and one left behind holds the card and the RAM the next
+// replica needs. Found before the group is signalled, while they are still
+// its descendants: after, they belong to init. Linux only; elsewhere none.
+func strays(pid int) []int {
+	entries, err := os.ReadDir("/proc")
+	if err != nil {
+		return nil
+	}
+	parent := map[int]int{}
+	group := map[int]int{}
+	for _, e := range entries {
+		p, err := strconv.Atoi(e.Name())
+		if err != nil {
+			continue
+		}
+		if pp, pg, ok := parentAndGroup(p); ok {
+			parent[p], group[p] = pp, pg
+		}
+	}
+	var out []int
+	for p := range parent {
+		if group[p] == pid || p == pid {
+			continue
+		}
+		// Bounded: no engine's tree is this deep, and a pid reused while
+		// /proc was read must not loop.
+		for q, n := parent[p], 0; q > 1 && n < 32; q, n = parent[q], n+1 {
+			if q == pid {
+				out = append(out, p)
+				break
+			}
+		}
+	}
+	return out
+}
+
+// parentAndGroup reads a process's parent and group from /proc.
+func parentAndGroup(pid int) (int, int, bool) {
+	b, err := os.ReadFile("/proc/" + strconv.Itoa(pid) + "/stat")
+	if err != nil {
+		return 0, 0, false
+	}
+	i := bytes.LastIndexByte(b, ')')
+	if i < 0 {
+		return 0, 0, false
+	}
+	f := strings.Fields(string(b[i+1:]))
+	if len(f) < 3 {
+		return 0, 0, false
+	}
+	pp, err1 := strconv.Atoi(f[1])
+	pg, err2 := strconv.Atoi(f[2])
+	return pp, pg, err1 == nil && err2 == nil
+}
+
+// signalStrays signals each stray, and its own group when it leads one.
+func signalStrays(pids []int, sig syscall.Signal) {
+	for _, p := range pids {
+		if _, pg, ok := parentAndGroup(p); ok && pg == p {
+			_ = syscall.Kill(-p, sig)
+			continue
+		}
+		_ = syscall.Kill(p, sig)
+	}
+}

internal/agent/supervisor/supervisor.go

@@ -582,10 +582,24 @@ func (s *Supervisor) Stop(ctx context.Context, id string) (err error) {
 	}
 
 	// Signal the group, not the process: engines fork workers that hold GPU
-	// memory, and those outlive a signal sent only to the leader.
+	// memory, and those outlive a signal sent only to the leader. And what
+	// left the group, found while it is still the leader's.
+	left := strays(pid)
 	if err := killGroup(pid, syscall.SIGTERM); err != nil && !errors.Is(err, os.ErrProcessDone) {
 		s.log.Warn("SIGTERM failed", "shard", id, "err", err)
 	}
+	signalStrays(left, syscall.SIGTERM)
+	defer func() {
+		// Given as long as the group to go; then killed.
+		deadline := time.Now().Add(5 * time.Second)
+		for time.Now().Before(deadline) && slices.ContainsFunc(left, processAlive) {
+			time.Sleep(100 * time.Millisecond)
+		}
+		if slices.ContainsFunc(left, processAlive) {
+			s.log.Warn("killing an engine's processes that left its group", "shard", id, "pids", left)
+			signalStrays(left, syscall.SIGKILL)
+		}
+	}()
 
 	// force kills the group outright. exec.Cmd's cancel does this for shards we
 	// started; an adopted shard has none, so signal its group directly.
@@ -598,6 +612,7 @@ func (s *Supervisor) Stop(ctx context.Context, id string) (err error) {
 		if err := killGroup(pid, syscall.SIGKILL); err != nil && !errors.Is(err, os.ErrProcessDone) {
 			s.log.Warn("SIGKILL failed", "shard", id, "err", err)
 		}
+		signalStrays(left, syscall.SIGKILL)
 	}
 
 	select {

internal/agent/supervisor/supervisor_test.go

@@ -8,6 +8,7 @@ import (
 	"log/slog"
 	"net"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"slices"
 	"strings"
@@ -981,3 +982,38 @@ func TestAnOutputFileIsEmptiedPastItsBound(t *testing.T) {
 		t.Errorf("a line written after the file was emptied was lost: %v", sh.Logs(8))
 	}
 }
+
+// An engine's worker in a session of its own, as Strata's is, is not in the
+// group a stop signals: it is found and stopped as well.
+func TestStopKillsAWorkerThatLeftTheGroup(t *testing.T) {
+	if _, err := os.Stat("/proc/self/stat"); err != nil {
+		t.Skip("needs /proc")
+	}
+	if _, err := exec.LookPath("setsid"); err != nil {
+		t.Skip("needs setsid")
+	}
+	s, _ := newSupervisor(t)
+	marker := filepath.Join(t.TempDir(), "worker.pid")
+	script := fmt.Sprintf(`setsid sh -c 'echo $$ > %s; sleep 30' & sleep 30`, marker)
+	if _, err := s.Start(t.Context(), "a", engines.ShardSpec{}, shellCommand(script)); err != nil {
+		t.Fatal(err)
+	}
+	var worker int
+	for deadline := time.Now().Add(3 * time.Second); time.Now().Before(deadline) && worker == 0; time.Sleep(10 * time.Millisecond) {
+		if b, err := os.ReadFile(marker); err == nil {
+			_, _ = fmt.Sscanf(strings.TrimSpace(string(b)), "%d", &worker)
+		}
+	}
+	if worker == 0 {
+		t.Fatal("the worker never started")
+	}
+	if err := s.Stop(t.Context(), "a"); err != nil {
+		t.Fatal(err)
+	}
+	for deadline := time.Now().Add(8 * time.Second); time.Now().Before(deadline); time.Sleep(50 * time.Millisecond) {
+		if !processAlive(worker) {
+			return
+		}
+	}
+	t.Errorf("the worker %d that left the group survived the stop", worker)
+}

internal/agent/upgrade.go

@@ -35,12 +35,25 @@ func (a *Agent) upgrade(ctx context.Context, m *llmgwv1.UpgradeAgent, out chan<-
 		select {
 		case out <- &llmgwv1.AgentMessage{Msg: &llmgwv1.AgentMessage_Upgrade{Upgrade: reply}}:
 		case <-ctx.Done():
+		case <-time.After(5 * time.Second):
 		}
 	}
+	// One at a time: a second request while one downloads would race it to
+	// the same file.
+	if !a.upgrading.CompareAndSwap(false, true) {
+		reply.Error = "an upgrade is already under way on this node"
+		send()
+		return
+	}
+	defer a.upgrading.Store(false)
 	a.log.Info("upgrading", "to", m.GetVersion(), "from", a.cfg.Version)
 	self, err := upgradeTarget()
 	if err == nil {
-		dctx, cancel := context.WithTimeout(ctx, 10*time.Minute)
+		// Not the stream's context: a stream that breaks while the release
+		// downloads — a control plane restarting, leadership moving — cancelled
+		// the upgrade with nobody told. The node registering again on the
+		// version is what the control plane watches for.
+		dctx, cancel := context.WithTimeout(context.WithoutCancel(ctx), upgradeDownload)
 		_, err = release.Install(dctx, nil, m.GetReleases(), m.GetVersion(), runtime.GOOS, runtime.GOARCH, self)
 		cancel()
 	}
@@ -53,6 +66,13 @@ func (a *Agent) upgrade(ctx context.Context, m *llmgwv1.UpgradeAgent, out chan<-
 	send()
 	a.log.Info("upgraded; restarting into the new version", "to", m.GetVersion())
 	// A moment for the reply to leave before the stream goes.
-	time.Sleep(500 * time.Millisecond)
+	time.Sleep(upgradeLinger)
 	exitForUpgrade()
 }
+
+// upgradeDownload bounds an upgrade's download; the control plane waits
+// longer (agentsvc.UpgradeWait). upgradeLinger is the moment its answer has
+// to leave before the agent exits; a variable so tests need not wait it.
+const upgradeDownload = 10 * time.Minute
+
+var upgradeLinger = 2 * time.Second

internal/agent/weights/fetch.go

@@ -90,14 +90,27 @@ var ErrNotLocal = errors.New("the weights are not on this node and the source sa
 // already cached, downloaded, or downloaded by another shard this one waited
 // for — since that is most of the difference between a replica that starts
 // in a minute and one that takes an hour.
-func (f *Fetcher) Ensure(ctx context.Context, source string) (path string, err error) {
+//
+// A source in a pickle format, or a set with such a file in it, is refused
+// before anything is fetched unless allowPickle; see Pickled.
+func (f *Fetcher) Ensure(ctx context.Context, source string, allowPickle bool) (path string, err error) {
+	return f.EnsureChecked(ctx, source, allowPickle, "")
+}
+
+// EnsureChecked is Ensure for a file whose sha256 the registry published: a
+// copy that is not it, downloaded or cached, is refused rather than served.
+// An empty sha256 checks nothing.
+func (f *Fetcher) EnsureChecked(ctx context.Context, source string, allowPickle bool, sha256 string) (path string, err error) {
 	ctx, span := obs.Tracer(tracerName).Start(ctx, "fetch weights",
 		trace.WithAttributes(attribute.String("llmgw.weights.source", redact(source))))
 	defer func() {
 		span.SetAttributes(attribute.String("llmgw.weights.path", path))
 		obs.End(span, err)
 	}()
-	return f.ensure(ctx, source)
+	if !allowPickle && !IsSet(source) && Pickled(source) {
+		return "", refusePickle(source)
+	}
+	return f.ensure(ctx, source, allowPickle, strings.ToLower(sha256))
 }
 
 // tracerName names the spans this package opens.
@@ -119,7 +132,7 @@ func redact(source string) string {
 	return u.String()
 }
 
-func (f *Fetcher) ensure(ctx context.Context, source string) (string, error) {
+func (f *Fetcher) ensure(ctx context.Context, source string, allowPickle bool, want string) (string, error) {
 	if source == "" {
 		return "", fmt.Errorf("no source given")
 	}
@@ -127,7 +140,7 @@ func (f *Fetcher) ensure(ctx context.Context, source string) (string, error) {
 	// file, and a set has to be handled before any of it.
 	if IsSet(source) {
 		outcome(ctx, "set")
-		return f.ensureSet(ctx, source)
+		return f.ensureSet(ctx, source, allowPickle)
 	}
 	if !isRemote(source) {
 		if !isPath(source) {
@@ -150,8 +163,13 @@ func (f *Fetcher) ensure(ctx context.Context, source string) (string, error) {
 		return "", err
 	}
 	if _, err := os.Stat(target); err == nil {
-		outcome(ctx, "cached")
-		return target, nil
+		if ok, err := f.cachedIs(target, want); err != nil {
+			return "", err
+		} else if ok {
+			outcome(ctx, "cached")
+			return target, nil
+		}
+		// Not the file the catalog names: fetched again below, and checked.
 	}
 
 	f.mu.Lock()
@@ -173,7 +191,7 @@ func (f *Fetcher) ensure(ctx context.Context, source string) (string, error) {
 	f.mu.Unlock()
 
 	outcome(ctx, "downloaded")
-	call.path, call.err = f.fetch(ctx, source, target)
+	call.path, call.err = f.fetchChecked(ctx, source, target, want)
 	close(call.done)
 
 	f.mu.Lock()
@@ -187,6 +205,80 @@ func (f *Fetcher) fetch(ctx context.Context, source, target string) (string, err
 	return f.fetchAs(ctx, source, source, target)
 }
 
+// fetchChecked is fetch for a file whose sha256 is known: a download that
+// is not it is deleted and refused, naming both, and one that is has its
+// checksum kept beside it so a cached copy is not read again at each start.
+func (f *Fetcher) fetchChecked(ctx context.Context, source, target, want string) (string, error) {
+	got, err := f.fetch(ctx, source, target)
+	if err != nil || want == "" {
+		return got, err
+	}
+	sum, err := fileSHA256(target)
+	if err != nil {
+		return "", err
+	}
+	if sum != want {
+		_ = os.Remove(target)
+		return "", fmt.Errorf("%s arrived with sha256 %s, and the registry published %s for it: refused and deleted",
+			redact(source), sum, want)
+	}
+	_ = writeChecksum(target, sum)
+	return target, nil
+}
+
+// cachedIs says whether a cached file is the one whose sha256 is want: by
+// the checksum kept beside it, or worked out once and then kept. One that
+// is not is deleted, to be fetched again. Any file is, when want is empty.
+func (f *Fetcher) cachedIs(target, want string) (bool, error) {
+	kept := readChecksum(target)
+	if want == "" || kept == want {
+		return true, nil
+	}
+	if kept != "" {
+		// Checked when it was fetched, as another file: the same address
+		// gives the same bytes again, and another model may be serving
+		// these. Refused, and left.
+		return false, fmt.Errorf("the copy of this file here has sha256 %s, as fetched, and the catalog names %s: refused",
+			kept, want)
+	}
+	sum, err := fileSHA256(target)
+	if err != nil {
+		return false, err
+	}
+	if sum == want {
+		_ = writeChecksum(target, sum)
+		return true, nil
+	}
+	if f.Log != nil {
+		f.Log.Warn("a cached file is not the one the catalog names; fetching it again",
+			"path", target, "sha256", sum, "want", want)
+	}
+	_ = os.Remove(checksumPath(target))
+	return false, os.Remove(target)
+}
+
+// checksumPath is where a cached file's sha256 is kept: beside it, hidden,
+// so no scan takes it for weights.
+func checksumPath(file string) string {
+	return filepath.Join(filepath.Dir(file), "."+filepath.Base(file)+".sha256")
+}
+
+func writeChecksum(file, sum string) error {
+	return os.WriteFile(checksumPath(file), []byte(sum+"\n"), 0o644) //nolint:gosec // a checksum, for anyone to read
+}
+
+func readChecksum(file string) string {
+	b, err := os.ReadFile(checksumPath(file)) //nolint:gosec // beside a file this fetcher wrote
+	if err != nil {
+		return ""
+	}
+	return strings.TrimSpace(string(b))
+}
+
+// ChecksumPath is where the sha256 of a cached file is kept, for whoever
+// deletes the file to delete with it.
+func ChecksumPath(file string) string { return checksumPath(file) }
+
 // fetchAs downloads one URL but reports progress under another name.
 //
 // The two differ for a set: the shards waiting on it asked for the version, not

internal/agent/weights/fetch_test.go

@@ -1,6 +1,8 @@
 package weights
 
 import (
+	"crypto/sha256"
+	"encoding/hex"
 	"errors"
 	"net/http"
 	"net/http/httptest"
@@ -37,7 +39,7 @@ func TestALocalPathIsUsedNeverCopied(t *testing.T) {
 	}
 	f := &Fetcher{CacheDir: t.TempDir()}
 
-	got, err := f.Ensure(t.Context(), path)
+	got, err := f.Ensure(t.Context(), path, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -53,7 +55,7 @@ func TestAMissingLocalPathSaysWhatIsWrong(t *testing.T) {
 	// The commonest setup mistake, and "no such file" from an engine twenty
 	// minutes into a load is a poor way to learn it.
 	f := &Fetcher{CacheDir: t.TempDir()}
-	_, err := f.Ensure(t.Context(), filepath.Join(t.TempDir(), "absent.gguf"))
+	_, err := f.Ensure(t.Context(), filepath.Join(t.TempDir(), "absent.gguf"), false)
 	if !errors.Is(err, ErrNotLocal) {
 		t.Fatalf("err = %v, want ErrNotLocal", err)
 	}
@@ -67,7 +69,7 @@ func TestARemoteFileIsFetchedOnceAndReused(t *testing.T) {
 	srv := serveBytes(t, []byte("the weights"), &hits)
 	f := &Fetcher{CacheDir: t.TempDir()}
 
-	first, err := f.Ensure(t.Context(), srv.URL+"/model.gguf")
+	first, err := f.Ensure(t.Context(), srv.URL+"/model.gguf", false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -76,7 +78,7 @@ func TestARemoteFileIsFetchedOnceAndReused(t *testing.T) {
 		t.Fatalf("fetched content = %q, err %v", body, err)
 	}
 
-	second, err := f.Ensure(t.Context(), srv.URL+"/model.gguf")
+	second, err := f.Ensure(t.Context(), srv.URL+"/model.gguf", false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -103,7 +105,7 @@ func TestConcurrentRequestsProduceOneDownload(t *testing.T) {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			paths[i], errs[i] = f.Ensure(t.Context(), srv.URL+"/model.gguf")
+			paths[i], errs[i] = f.Ensure(t.Context(), srv.URL+"/model.gguf", false)
 		}()
 	}
 	wg.Wait()
@@ -139,7 +141,7 @@ func TestAPartialDownloadIsNeverVisibleAsTheModel(t *testing.T) {
 
 	cache := t.TempDir()
 	f := &Fetcher{CacheDir: cache}
-	if _, err := f.Ensure(t.Context(), srv.URL+"/model.gguf"); err == nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/model.gguf", false); err == nil {
 		t.Fatal("a truncated download was reported as success")
 	}
 	entries, _ := os.ReadDir(cache)
@@ -169,7 +171,7 @@ func TestAnInterruptedDownloadResumes(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := f.Ensure(t.Context(), srv.URL+"/model.gguf")
+	got, err := f.Ensure(t.Context(), srv.URL+"/model.gguf", false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -232,7 +234,7 @@ func TestProgressIsReportedWithAPercentage(t *testing.T) {
 		CacheDir:   t.TempDir(),
 		OnProgress: func(p Progress) { seen = append(seen, p) },
 	}
-	if _, err := f.Ensure(t.Context(), srv.URL+"/model.gguf"); err != nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/model.gguf", false); err != nil {
 		t.Fatal(err)
 	}
 	if len(seen) == 0 {
@@ -254,7 +256,7 @@ func TestPercentIsUnknownRatherThanZeroWithoutATotal(t *testing.T) {
 
 func TestNoCacheDirectoryIsAClearRefusal(t *testing.T) {
 	f := &Fetcher{}
-	_, err := f.Ensure(t.Context(), "https://example.invalid/model.gguf")
+	_, err := f.Ensure(t.Context(), "https://example.invalid/model.gguf", false)
 	if err == nil || !strings.Contains(err.Error(), "cache directory") {
 		t.Errorf("err = %v, want a complaint about the cache directory", err)
 	}
@@ -269,7 +271,7 @@ func TestABareModelIdIsLeftToTheEngine(t *testing.T) {
 		"Qwen/Qwen2.5-7B-Instruct",
 		"meta-llama/Llama-3.3-70B-Instruct",
 	} {
-		got, err := f.Ensure(t.Context(), id)
+		got, err := f.Ensure(t.Context(), id, false)
 		if err != nil {
 			t.Errorf("%s was refused: %v", id, err)
 		}
@@ -283,7 +285,79 @@ func TestAnAbsolutePathThatIsMissingIsStillAnError(t *testing.T) {
 	// The other half: an operator writing a path means a file, and a missing
 	// one should be said plainly rather than handed to an engine.
 	f := &Fetcher{CacheDir: t.TempDir()}
-	if _, err := f.Ensure(t.Context(), "/models/definitely-not-here.gguf"); !errors.Is(err, ErrNotLocal) {
+	if _, err := f.Ensure(t.Context(), "/models/definitely-not-here.gguf", false); !errors.Is(err, ErrNotLocal) {
 		t.Errorf("err = %v, want ErrNotLocal", err)
 	}
 }
+
+// A file whose sha256 the registry published is served only as that file:
+// changed upstream after the model was added, it is refused with both
+// checksums named, and a cached copy that is not it is fetched again.
+func TestAFileThatIsNotWhatTheRegistryPublishedIsRefused(t *testing.T) {
+	body := "the weights as published"
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+		_, _ = w.Write([]byte(body))
+	}))
+	defer srv.Close()
+	sum := sha256.Sum256([]byte(body))
+	want := hex.EncodeToString(sum[:])
+	f := &Fetcher{CacheDir: t.TempDir()}
+	src := srv.URL + "/model.gguf"
+
+	path, err := f.EnsureChecked(t.Context(), src, false, strings.ToUpper(want))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if readChecksum(path) != want {
+		t.Errorf("the checksum was not kept beside it: %q", readChecksum(path))
+	}
+
+	// The cached copy changed under it: fetched again, and the right one kept.
+	if err := os.WriteFile(path, []byte("tampered"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	_ = os.Remove(checksumPath(path))
+	if _, err := f.EnsureChecked(t.Context(), src, false, want); err != nil {
+		t.Fatal(err)
+	}
+	if b, _ := os.ReadFile(path); string(b) != body {
+		t.Errorf("the cached copy that was not it was served: %q", b)
+	}
+
+	// Upstream changed after the model was added.
+	body = "weights someone replaced"
+	f2 := &Fetcher{CacheDir: t.TempDir()}
+	_, err = f2.EnsureChecked(t.Context(), src, false, want)
+	if err == nil || !strings.Contains(err.Error(), want) || !strings.Contains(err.Error(), "sha256") {
+		t.Fatalf("not refused, or without both checksums: %v", err)
+	}
+	if _, err := os.Stat(CachePathFor(f2.CacheDir, src)); !os.IsNotExist(err) {
+		t.Error("the file that was not it was kept")
+	}
+	// With nothing to check against, it is fetched as before.
+	if _, err := f2.Ensure(t.Context(), src, false); err != nil {
+		t.Error(err)
+	}
+}
+
+// A cached file checked when it was fetched, that another model names with
+// another checksum, is refused and left for the model it is.
+func TestACheckedFileAnotherChecksumNamesIsRefusedAndLeft(t *testing.T) {
+	body := "the weights"
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) { _, _ = w.Write([]byte(body)) }))
+	defer srv.Close()
+	sum := sha256.Sum256([]byte(body))
+	f := &Fetcher{CacheDir: t.TempDir()}
+	src := srv.URL + "/m.gguf"
+	path, err := f.EnsureChecked(t.Context(), src, false, hex.EncodeToString(sum[:]))
+	if err != nil {
+		t.Fatal(err)
+	}
+	wrong := strings.Repeat("0", 64)
+	if _, err := f.EnsureChecked(t.Context(), src, false, wrong); err == nil || !strings.Contains(err.Error(), wrong) {
+		t.Fatalf("not refused: %v", err)
+	}
+	if b, err := os.ReadFile(path); err != nil || string(b) != body {
+		t.Errorf("the checked file was not left: %v", err)
+	}
+}

internal/agent/weights/pickle.go

@@ -0,0 +1,43 @@
+package weights
+
+import (
+	"errors"
+	"fmt"
+	"path"
+	"strings"
+)
+
+// Weights in Python's pickle format are a program as much as a file: loading
+// one runs whatever it says, as the engine's user, on the node. That is how
+// the malicious models found on Hugging Face work, and nothing in the file's
+// name or size says so. safetensors and GGUF are only tensors and are read,
+// never run, so those are what a node fetches unless the catalog says
+// otherwise for a model, with allow_pickle, on purpose.
+
+// pickleExts are the extensions of PyTorch's pickle formats, and of pickle
+// itself. A .bin beside safetensors is the same model in pickle form.
+var pickleExts = []string{".bin", ".pt", ".pt2", ".pth", ".ckpt", ".pkl", ".pickle"}
+
+// Pickled reports whether a file name or URL is in a pickle format.
+func Pickled(name string) bool {
+	// A query or a fragment is not the file's name, on a URL or an hf:
+	// source alike: model.bin?download=true is still model.bin.
+	if i := strings.IndexAny(name, "?#"); i >= 0 {
+		name = name[:i]
+	}
+	ext := strings.ToLower(path.Ext(name))
+	for _, e := range pickleExts {
+		if ext == e {
+			return true
+		}
+	}
+	return false
+}
+
+// ErrPickle is a source refused for being in a pickle format.
+var ErrPickle = errors.New("weights in a pickle format run code when they are loaded")
+
+func refusePickle(name string) error {
+	return fmt.Errorf("%w: %s is refused; use the model's safetensors or GGUF, or set allow_pickle: true "+
+		"on the model if it was checked and has no other form", ErrPickle, redact(name))
+}

internal/agent/weights/pickle_test.go

@@ -0,0 +1,66 @@
+package weights
+
+import (
+	"errors"
+	"sync/atomic"
+	"testing"
+)
+
+func TestPickleFormatsAreKnownByTheirNames(t *testing.T) {
+	for name, want := range map[string]bool{
+		"pytorch_model.bin": true, "model.ckpt": true, "x.PT": true, "w.pth": true, "a.pkl": true,
+		"https://h/r/resolve/main/model.ckpt?download=true": true,
+		"hf:o/r/model.bin?download=true":                    true, "hf:o/r/model.ckpt#x": true, "m.pt2": true,
+		"model.safetensors": false, "m-Q4_K_M.gguf": false, "Qwen/Qwen2.5-7B-Instruct": false,
+		"config.json": false, "": false,
+	} {
+		if got := Pickled(name); got != want {
+			t.Errorf("Pickled(%q) = %v, want %v", name, got, want)
+		}
+	}
+}
+
+func TestAPickleFileIsRefusedBeforeItIsFetched(t *testing.T) {
+	var hits atomic.Int64
+	srv := serveBytes(t, []byte("not really a pickle"), &hits)
+	f := &Fetcher{CacheDir: t.TempDir()}
+
+	_, err := f.Ensure(t.Context(), srv.URL+"/model.ckpt", false)
+	if !errors.Is(err, ErrPickle) {
+		t.Fatalf("a .ckpt was not refused: %v", err)
+	}
+	if hits.Load() != 0 {
+		t.Errorf("the refused file was fetched %d times", hits.Load())
+	}
+	if _, err := f.Ensure(t.Context(), srv.URL+"/model.ckpt", true); err != nil {
+		t.Errorf("allowed, the .ckpt was still refused: %v", err)
+	}
+}
+
+func TestASetWithAPickleFileIsRefusedWhole(t *testing.T) {
+	f, srv, hits := mirrorOf(t, map[string]string{
+		"pytorch_model.bin": "pickle",
+		"config.json":       "{}",
+	})
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); !errors.Is(err, ErrPickle) {
+		t.Fatalf("a set holding pytorch_model.bin was not refused: %v", err)
+	}
+	if *hits != 0 {
+		t.Errorf("%d files of the refused set were fetched", *hits)
+	}
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", true); err != nil {
+		t.Errorf("allowed, the set was still refused: %v", err)
+	}
+}
+
+func TestASetAlreadyHereIsLookedAtAgain(t *testing.T) {
+	// Fetched once for a model that allowed pickles, or before they were
+	// refused: another asking for it without leave is refused all the same.
+	f, srv, _ := mirrorOf(t, map[string]string{"pytorch_model.bin": "pickle", "config.json": "{}"})
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", true); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); !errors.Is(err, ErrPickle) {
+		t.Errorf("a set already on the node was not looked at: %v", err)
+	}
+}

internal/agent/weights/set.go

@@ -46,7 +46,7 @@ type manifest struct {
 // The whole set or nothing. A directory with three of four shards in it loads
 // as a broken model rather than failing to load, so a partial set is left
 // unfinished under its temporary name and the next attempt starts again.
-func (f *Fetcher) ensureSet(ctx context.Context, source string) (string, error) {
+func (f *Fetcher) ensureSet(ctx context.Context, source string, allowPickle bool) (string, error) {
 	dir, err := f.cachePath(strings.TrimSuffix(source, "/"))
 	if err != nil {
 		return "", err
@@ -56,6 +56,16 @@ func (f *Fetcher) ensureSet(ctx context.Context, source string) (string, error)
 	// exactly the failure the marker exists to prevent.
 	done := filepath.Join(dir, ".complete")
 	if _, err := os.Stat(done); err == nil {
+		// Already here, maybe fetched for a model that allowed pickles, or
+		// before they were refused: looked at again, not trusted.
+		if !allowPickle {
+			entries, _ := os.ReadDir(dir)
+			for _, e := range entries {
+				if Pickled(e.Name()) {
+					return "", refusePickle(source + e.Name())
+				}
+			}
+		}
 		return dir, nil
 	}
 
@@ -66,6 +76,15 @@ func (f *Fetcher) ensureSet(ctx context.Context, source string) (string, error)
 	if len(m.Files) == 0 {
 		return "", fmt.Errorf("%s holds no files", source)
 	}
+	// Refused whole rather than skipped: an engine given the directory
+	// loads the pickle when there is no safetensors beside it.
+	if !allowPickle {
+		for _, file := range m.Files {
+			if Pickled(file.Name) {
+				return "", refusePickle(source + file.Name)
+			}
+		}
+	}
 
 	if err := os.MkdirAll(dir, 0o755); err != nil {
 		return "", err

internal/agent/weights/set_test.go

@@ -53,7 +53,7 @@ func TestASetIsFetchedIntoOneDirectory(t *testing.T) {
 		"config.json":                      "{}",
 	})
 
-	got, err := f.Ensure(t.Context(), srv.URL+"/m/v/")
+	got, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -74,11 +74,11 @@ func TestASetIsFetchedIntoOneDirectory(t *testing.T) {
 func TestAFinishedSetIsNotFetchedAgain(t *testing.T) {
 	f, srv, hits := mirrorOf(t, map[string]string{"a.gguf": "aaaa", "b.gguf": "bb"})
 
-	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/"); err != nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); err != nil {
 		t.Fatal(err)
 	}
 	after := *hits
-	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/"); err != nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); err != nil {
 		t.Fatal(err)
 	}
 	if *hits != after {
@@ -100,7 +100,7 @@ func TestAHalfFetchedSetIsNotTreatedAsFinished(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	got, err := f.Ensure(t.Context(), srv.URL+"/m/v/")
+	got, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -117,7 +117,7 @@ func TestAFileAlreadyThereAtTheRightSizeIsNotRefetched(t *testing.T) {
 	_ = os.MkdirAll(dir, 0o755)
 	_ = os.WriteFile(filepath.Join(dir, "a.gguf"), []byte("aaaa"), 0o644)
 
-	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/"); err != nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); err != nil {
 		t.Fatal(err)
 	}
 	// Resuming a set means not paying for the shards that already landed.
@@ -133,7 +133,7 @@ func TestAFilenameThatEscapesTheDirectoryIsRefused(t *testing.T) {
 	defer srv.Close()
 	f := &Fetcher{CacheDir: t.TempDir()}
 
-	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/")
+	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false)
 	// The mirror is a place an operator copies files into by hand, so what it
 	// reports is not automatically safe to join onto a path.
 	if err == nil || !strings.Contains(err.Error(), "offered a file named") {
@@ -148,7 +148,7 @@ func TestADirectoryListingIsNotAManifest(t *testing.T) {
 	defer srv.Close()
 	f := &Fetcher{CacheDir: t.TempDir()}
 
-	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/")
+	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false)
 	// "invalid character '<'" sends somebody looking at the wrong thing.
 	if err == nil || !strings.Contains(err.Error(), "has to be a mirror version") {
 		t.Errorf("the reason should name the cause, got %v", err)
@@ -182,12 +182,12 @@ func TestASetFileThatDoesNotMatchTheMirrorsChecksumIsRefused(t *testing.T) {
 	}))
 	t.Cleanup(srv.Close)
 	f := &Fetcher{CacheDir: t.TempDir()}
-	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/"); err == nil || !strings.Contains(err.Error(), "sha256") {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); err == nil || !strings.Contains(err.Error(), "sha256") {
 		t.Fatalf("a damaged shard was accepted: %v", err)
 	}
 	served = good
 	// The size differs, so it is fetched again; this time it matches.
-	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/"); err != nil {
+	if _, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false); err != nil {
 		t.Fatalf("the shard as mirrored: %v", err)
 	}
 }
@@ -198,7 +198,7 @@ func TestASetStillDownloadingOnTheMirrorSaysSo(t *testing.T) {
 	}))
 	t.Cleanup(srv.Close)
 	f := &Fetcher{CacheDir: t.TempDir()}
-	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/")
+	_, err := f.Ensure(t.Context(), srv.URL+"/m/v/", false)
 	if err == nil || !strings.Contains(err.Error(), "not complete on the mirror yet") ||
 		!strings.Contains(err.Error(), "model-00002-of-00002") {
 		t.Fatalf("got %v", err)

internal/agent/weights/trace_test.go

@@ -13,7 +13,7 @@ func TestAFetchSaysInItsTraceWhetherItDownloadedAndHowMuch(t *testing.T) {
 	f := &Fetcher{CacheDir: t.TempDir()}
 	src := strings.Replace(srv.URL, "http://", "http://user:secret@", 1) + "/m/model.gguf?token=hunter2"
 
-	if _, err := f.Ensure(t.Context(), src); err != nil {
+	if _, err := f.Ensure(t.Context(), src, false); err != nil {
 		t.Fatal(err)
 	}
 	fetch := rec.One(t, [16]byte{}, "fetch weights")
@@ -30,7 +30,7 @@ func TestAFetchSaysInItsTraceWhetherItDownloadedAndHowMuch(t *testing.T) {
 	}
 
 	// The second start on this node finds it here.
-	if _, err := f.Ensure(t.Context(), src); err != nil {
+	if _, err := f.Ensure(t.Context(), src, false); err != nil {
 		t.Fatal(err)
 	}
 	again := rec.Named("fetch weights")

internal/cli/answercache.go

@@ -5,6 +5,8 @@ import (
 	"time"
 
 	"github.com/spf13/cobra"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
 )
 
 func newAnswerCacheCmd(open opener) *cobra.Command {
@@ -12,6 +14,7 @@ func newAnswerCacheCmd(open opener) *cobra.Command {
 		project   string
 		ttl       time.Duration
 		anyAnswer bool
+		similar   float64
 		off       bool
 	)
 	cmd := &cobra.Command{
@@ -28,15 +31,25 @@ func newAnswerCacheCmd(open opener) *cobra.Command {
 			"a request continuing a stored conversation or under a guardrails no_store\n" +
 			"policy. The guardrails judge a reused answer as they judge any other.\n\n" +
 			"Off for every project until this is run. Without --ttl or --off, says how\n" +
-			"it stands. The answers are held in memory, router.cache bounds how much.",
+			"it stands. The answers are held in memory, router.cache bounds how much.\n\n" +
+			"--similar also answers a chat question that is like one already answered:\n" +
+			"its last user message embedded by router.cache.embedding_model, and given\n" +
+			"the answer whose question reaches that cosine similarity (0.95 is strict,\n" +
+			"0.9 looser), as x-llmgw-cache: similar. The system prompt, the earlier\n" +
+			"turns, tools and the sampling settings must still be the same.",
 		Example: "  llmgw keys cache --project Acme/ml/train --ttl 1h\n" +
 			"  llmgw keys cache --project Acme/ml/eval --ttl 24h --any\n" +
+			"  llmgw keys cache --project Acme/support/desk --ttl 24h --similar 0.95\n" +
 			"  llmgw keys cache --project Acme/ml/train --off",
 		Args: cobra.NoArgs,
 		RunE: func(cmd *cobra.Command, _ []string) error {
 			switch {
-			case off && (ttl != 0 || anyAnswer):
-				return fmt.Errorf("--off, or --ttl with --any: not both")
+			case off && (ttl != 0 || anyAnswer || similar != 0):
+				return fmt.Errorf("--off, or --ttl with --any or --similar: not both")
+			case similar < 0 || similar > 1:
+				return fmt.Errorf("--similar is a cosine similarity between 0 and 1, like 0.95")
+			case similar != 0 && ttl == 0:
+				return fmt.Errorf("--similar goes with --ttl: say how long answers are reused")
 			case ttl < 0:
 				return fmt.Errorf("--ttl is how long an answer is reused, like 1h")
 			case ttl > 0 && ttl < time.Second:
@@ -54,7 +67,7 @@ func newAnswerCacheCmd(open opener) *cobra.Command {
 				return err
 			}
 			if off || ttl > 0 {
-				if err := s.SetAnswerCache(cmd.Context(), p.ID, ttl, anyAnswer); err != nil {
+				if err := s.SetAnswerCache(cmd.Context(), p.ID, store.AnswerCache{TTL: ttl, Any: anyAnswer, Similar: similar}); err != nil {
 					return err
 				}
 			}
@@ -71,6 +84,9 @@ func newAnswerCacheCmd(open opener) *cobra.Command {
 				fmt.Fprintf(cmd.OutOrStdout(), "%s reuses answers for %s: those asked at temperature 0 or with a seed, "+
 					"and embeddings, rerank and score.\n", p.Path, c.TTL)
 			}
+			if c.TTL > 0 && c.Similar > 0 {
+				fmt.Fprintf(cmd.OutOrStdout(), "Chat questions reaching %.2f similarity to one answered get its answer too.\n", c.Similar)
+			}
 			if off || ttl > 0 {
 				fmt.Fprintln(cmd.OutOrStdout(), "Gateways see the change within 30 seconds.")
 			}
@@ -80,6 +96,7 @@ func newAnswerCacheCmd(open opener) *cobra.Command {
 	cmd.Flags().StringVar(&project, "project", "", "project: id, path or unique name")
 	cmd.Flags().DurationVar(&ttl, "ttl", 0, "how long an answer is reused, like 1h")
 	cmd.Flags().BoolVar(&anyAnswer, "any", false, "reuse sampled answers too, not only reproducible ones")
+	cmd.Flags().Float64Var(&similar, "similar", 0, "also answer chat questions this similar to one answered, like 0.95")
 	cmd.Flags().BoolVar(&off, "off", false, "stop reusing answers for this project")
 	return cmd
 }

internal/cli/bench.go

@@ -150,6 +150,7 @@ func newBenchCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
 	f.DurationVar(&cfg.SLO.TPOTp99, "tpot-p99", cfg.SLO.TPOTp99, "per-output-token target")
 	f.BoolVar(&save, "save", false,
 		"record the capacity against the model and profile, so the number outlives this terminal")
+	cmd.AddCommand(newBenchOverheadCmd(asJSON))
 	return cmd
 }
 

internal/cli/bench_overhead.go

@@ -0,0 +1,421 @@
+package cli
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log/slog"
+	"net"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"slices"
+	"sort"
+	"strings"
+	"sync"
+	"syscall"
+	"text/tabwriter"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/config"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/guard"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/router"
+	storepkg "gitea.mynodes.xyz/ilker/llmgw/internal/store"
+)
+
+// What llmgw adds to a request, measured: the same load straight at an
+// engine that answers at once, and through the gateway in front of it —
+// bare, with authentication and usage accounting, and with the guardrails'
+// pattern checks besides. The engine's own time is the same on both paths,
+// so what differs is the gateway's.
+//
+// Everything runs in this process, on loopback: no cluster, no GPU, and the
+// numbers are this machine's. On a machine shared with other work (a VM on
+// an oversubscribed host) they move with it; compare modes run together,
+// not figures from different runs.
+
+// overheadMode is one way a request reaches the engine.
+type overheadMode struct {
+	name        string
+	gateway     bool
+	auth, guard bool
+}
+
+var overheadModes = []overheadMode{
+	{name: "direct"},
+	{name: "gateway", gateway: true},
+	{name: "gateway+auth", gateway: true, auth: true},
+	{name: "gateway+auth+guard", gateway: true, auth: true, guard: true},
+}
+
+// overheadStep is one mode at one request rate.
+type overheadStep struct {
+	Mode     string        `json:"mode"`
+	Rate     int           `json:"rate"`
+	Sent     int           `json:"sent"`
+	Failed   int           `json:"failed"`
+	P50      time.Duration `json:"p50"`
+	P99      time.Duration `json:"p99"`
+	AddedP50 time.Duration `json:"added_p50"`
+	AddedP99 time.Duration `json:"added_p99"`
+	// CPUPer1k is the process's CPU time per thousand requests beyond what
+	// the direct mode spent at the same rate: the gateway's.
+	CPUPer1k time.Duration `json:"cpu_per_1k"`
+	cpu      time.Duration
+}
+
+func newBenchOverheadCmd(asJSON *bool) *cobra.Command {
+	var (
+		rates []int
+		each  time.Duration
+	)
+	cmd := &cobra.Command{
+		Use:   "overhead",
+		Short: "Measure what the gateway adds to a request, against an engine that answers at once",
+		Long: "Runs an engine that answers at once and a gateway in front of it, in this\n" +
+			"process on loopback, and sends the same load at each rate straight to the\n" +
+			"engine and through the gateway: bare, with authentication and usage\n" +
+			"accounting, and with the guardrails' pattern checks too. Reports each\n" +
+			"request's latency at p50 and p99, what the gateway added to it, and the\n" +
+			"gateway's CPU time per thousand requests.\n\n" +
+			"Needs no cluster. The figures are this machine's: on one shared with other\n" +
+			"work they move with it, so compare the modes of one run, and note the\n" +
+			"machine's load beside any figure you keep.",
+		Args: cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			steps, err := runOverhead(cmd.Context(), rates, each)
+			if err != nil {
+				return err
+			}
+			if *asJSON {
+				return json.NewEncoder(cmd.OutOrStdout()).Encode(steps)
+			}
+			printOverhead(cmd.OutOrStdout(), steps)
+			return nil
+		},
+	}
+	f := cmd.Flags()
+	f.IntSliceVar(&rates, "rates", []int{100, 500, 1000, 2000}, "requests a second to send, one step each")
+	f.DurationVar(&each, "each", 3*time.Second, "how long each step sends for")
+	return cmd
+}
+
+func printOverhead(w io.Writer, steps []overheadStep) {
+	tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', 0)
+	fmt.Fprintln(tw, "MODE\tRATE/S\tSENT\tFAILED\tP50\tP99\t+P50\t+P99\tCPU/1K REQ")
+	for _, s := range steps {
+		added := func(d time.Duration) string {
+			if s.Mode == "direct" {
+				return "-"
+			}
+			return msOf(d)
+		}
+		cpu := "-"
+		if s.Mode != "direct" {
+			cpu = msOf(s.CPUPer1k)
+		}
+		fmt.Fprintf(tw, "%s\t%d\t%d\t%d\t%s\t%s\t%s\t%s\t%s\n", s.Mode, s.Rate, s.Sent, s.Failed,
+			msOf(s.P50), msOf(s.P99), added(s.AddedP50), added(s.AddedP99), cpu)
+	}
+	_ = tw.Flush()
+	fmt.Fprintf(w, "\n%d CPUs, %s. Loopback, in one process: the figures are this machine's.\n",
+		runtime.NumCPU(), loadAverage())
+}
+
+func msOf(d time.Duration) string { return fmt.Sprintf("%.2fms", float64(d)/float64(time.Millisecond)) }
+
+// loadAverage is the machine's, where it can be read, to keep beside the
+// figures.
+func loadAverage() string {
+	if b, err := os.ReadFile("/proc/loadavg"); err == nil {
+		if f := strings.Fields(string(b)); len(f) >= 3 {
+			return "load " + strings.Join(f[:3], " ")
+		}
+	}
+	// macOS: "{ 1.23 1.10 0.98 }".
+	if b, err := exec.Command("sysctl", "-n", "vm.loadavg").Output(); err == nil {
+		if f := strings.Fields(strings.Trim(strings.TrimSpace(string(b)), "{}")); len(f) >= 3 {
+			return "load " + strings.Join(f[:3], " ")
+		}
+	}
+	return "load not read"
+}
+
+// runOverhead measures every mode at every rate.
+func runOverhead(ctx context.Context, rates []int, each time.Duration) ([]overheadStep, error) {
+	engine, err := instantEngine()
+	if err != nil {
+		return nil, err
+	}
+	defer engine.Close()
+	dir, err := os.MkdirTemp("", "llmgw-overhead-")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(dir)
+
+	type target struct {
+		url, key string
+		stop     func()
+	}
+	targets := map[string]target{}
+	defer func() {
+		for _, t := range targets {
+			if t.stop != nil {
+				t.stop()
+			}
+		}
+	}()
+	for _, m := range overheadModes {
+		if !m.gateway {
+			targets[m.name] = target{url: engine.URL}
+			continue
+		}
+		url, key, stop, err := overheadGateway(ctx, engine.URL, filepath.Join(dir, m.name+".db"), m)
+		if err != nil {
+			return nil, fmt.Errorf("%s: %w", m.name, err)
+		}
+		targets[m.name] = target{url: url, key: key, stop: stop}
+	}
+
+	client := &http.Client{Transport: &http.Transport{MaxIdleConns: 1024, MaxIdleConnsPerHost: 1024}, Timeout: 30 * time.Second}
+	var out []overheadStep
+	for _, rate := range rates {
+		var direct overheadStep
+		for _, m := range overheadModes {
+			t := targets[m.name]
+			s := loadStep(ctx, client, t.url, t.key, rate, each)
+			s.Mode = m.name
+			if m.name == "direct" {
+				direct = s
+			} else {
+				s.AddedP50, s.AddedP99 = max(0, s.P50-direct.P50), max(0, s.P99-direct.P99)
+				if s.Sent > 0 {
+					s.CPUPer1k = max(0, s.cpu-direct.cpu) * 1000 / time.Duration(s.Sent)
+				}
+			}
+			out = append(out, s)
+		}
+	}
+	return out, nil
+}
+
+// loadStep sends rate requests a second for d, each in its own goroutine,
+// and measures each one's latency and the process's CPU meanwhile.
+func loadStep(ctx context.Context, client *http.Client, url, key string, rate int, d time.Duration) overheadStep {
+	s := overheadStep{Rate: rate}
+	body := []byte(`{"model":"bench","max_tokens":8,"messages":[{"role":"user","content":"What is the capital of France?"}]}`)
+	var (
+		mu    sync.Mutex
+		lat   []time.Duration
+		wg    sync.WaitGroup
+		total = int(float64(rate) * d.Seconds())
+	)
+	interval := time.Second / time.Duration(max(rate, 1))
+	cpu0 := processCPU()
+	start := time.Now()
+	for i := range total {
+		if ctx.Err() != nil {
+			break
+		}
+		if wait := time.Until(start.Add(time.Duration(i) * interval)); wait > 0 {
+			time.Sleep(wait)
+		}
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			req, _ := http.NewRequestWithContext(ctx, http.MethodPost, url+"/v1/chat/completions", bytes.NewReader(body))
+			req.Header.Set("Content-Type", "application/json")
+			if key != "" {
+				req.Header.Set("Authorization", "Bearer "+key)
+			}
+			t := time.Now()
+			resp, err := client.Do(req)
+			ok := err == nil && resp.StatusCode == http.StatusOK
+			if resp != nil {
+				_, _ = io.Copy(io.Discard, resp.Body)
+				resp.Body.Close()
+			}
+			el := time.Since(t)
+			mu.Lock()
+			s.Sent++
+			if ok {
+				lat = append(lat, el)
+			} else {
+				s.Failed++
+			}
+			mu.Unlock()
+		}()
+	}
+	wg.Wait()
+	s.cpu = processCPU() - cpu0
+	s.P50, s.P99 = percentile(lat, 0.50), percentile(lat, 0.99)
+	return s
+}
+
+func percentile(ds []time.Duration, p float64) time.Duration {
+	if len(ds) == 0 {
+		return 0
+	}
+	ds = slices.Clone(ds)
+	sort.Slice(ds, func(i, j int) bool { return ds[i] < ds[j] })
+	i := int(p * float64(len(ds)-1))
+	return ds[i]
+}
+
+// processCPU is the CPU time this process has used, user and system.
+func processCPU() time.Duration {
+	var ru syscall.Rusage
+	if err := syscall.Getrusage(syscall.RUSAGE_SELF, &ru); err != nil {
+		return 0
+	}
+	return time.Duration(ru.Utime.Nano() + ru.Stime.Nano())
+}
+
+// instantEngine is an OpenAI-compatible engine that answers at once, with
+// the metrics the router scrapes.
+func instantEngine() (*httpServer, error) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("GET /metrics", func(w http.ResponseWriter, _ *http.Request) {
+		fmt.Fprint(w, "# TYPE vllm:num_requests_running gauge\nvllm:num_requests_running 0\n"+
+			"# TYPE vllm:num_requests_waiting gauge\nvllm:num_requests_waiting 0\n"+
+			"# TYPE vllm:kv_cache_usage_perc gauge\nvllm:kv_cache_usage_perc 0.1\n")
+	})
+	mux.HandleFunc("GET /health", func(w http.ResponseWriter, _ *http.Request) { w.WriteHeader(http.StatusOK) })
+	mux.HandleFunc("POST /v1/chat/completions", func(w http.ResponseWriter, r *http.Request) {
+		_, _ = io.Copy(io.Discard, r.Body)
+		w.Header().Set("Content-Type", "application/json")
+		fmt.Fprint(w, `{"id":"b","object":"chat.completion","model":"bench","choices":[{"index":0,"message":{"role":"assistant","content":"Paris."},"finish_reason":"stop"}],"usage":{"prompt_tokens":14,"completion_tokens":2,"total_tokens":16}}`)
+	})
+	return serveLoopback(mux)
+}
+
+// httpServer is a handler served on a loopback port.
+type httpServer struct {
+	URL string
+	srv *http.Server
+}
+
+func (s *httpServer) Close() { _ = s.srv.Close() }
+
+func serveLoopback(h http.Handler) (*httpServer, error) {
+	ln, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		return nil, err
+	}
+	srv := &http.Server{Handler: h, ReadHeaderTimeout: 10 * time.Second}
+	go func() { _ = srv.Serve(ln) }()
+	return &httpServer{URL: "http://" + ln.Addr().String(), srv: srv}, nil
+}
+
+// overheadGateway starts a gateway in front of the engine as the mode asks,
+// and returns its address and, with auth, a key.
+func overheadGateway(ctx context.Context, engineURL, storePath string, m overheadMode) (string, string, func(), error) {
+	cfg := config.Default()
+	cfg.Listen = "127.0.0.1:0"
+	cfg.Router.ScrapeInterval = 200 * time.Millisecond
+	cfg.Endpoints = []config.Endpoint{{ID: "bench", URL: engineURL, Models: []string{"bench"}}}
+	key := ""
+	if m.auth {
+		var err error
+		if key, err = overheadKey(ctx, storePath); err != nil {
+			return "", "", nil, err
+		}
+		cfg.Auth.Enabled, cfg.Auth.Store = true, storePath
+		// Limits would measure themselves refusing: off.
+		cfg.Auth.DefaultRPM, cfg.Auth.DefaultTPM = 0, 0
+	}
+	rt, err := router.New(cfg, slog.New(slog.DiscardHandler))
+	if err != nil {
+		return "", "", nil, err
+	}
+	if m.guard {
+		g, err := baselineGuard()
+		if err != nil {
+			return "", "", nil, err
+		}
+		rt.SetGuard(g)
+	}
+	rctx, cancel := context.WithCancel(ctx)
+	rt.Start(rctx)
+	srv, err := serveLoopback(rt.Handler())
+	if err != nil {
+		cancel()
+		return "", "", nil, err
+	}
+	stop := func() { srv.Close(); cancel(); rt.Stop() }
+	// Ready once a request goes through: the endpoint is scraped first.
+	deadline := time.Now().Add(10 * time.Second)
+	for {
+		body := `{"model":"bench","messages":[{"role":"user","content":"hi"}]}`
+		req, _ := http.NewRequestWithContext(ctx, http.MethodPost, srv.URL+"/v1/chat/completions", strings.NewReader(body))
+		req.Header.Set("Content-Type", "application/json")
+		if key != "" {
+			req.Header.Set("Authorization", "Bearer "+key)
+		}
+		resp, err := http.DefaultClient.Do(req)
+		if err == nil {
+			_, _ = io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			if resp.StatusCode == http.StatusOK {
+				return srv.URL, key, stop, nil
+			}
+		}
+		if time.Now().After(deadline) {
+			stop()
+			status := "no answer"
+			if err == nil {
+				status = resp.Status
+			}
+			return "", "", nil, fmt.Errorf("the gateway did not serve within 10s (%s)", status)
+		}
+		time.Sleep(100 * time.Millisecond)
+	}
+}
+
+// overheadKey makes a store with one project and a key in it.
+func overheadKey(ctx context.Context, path string) (string, error) {
+	st, err := storepkg.Open(ctx, path)
+	if err != nil {
+		return "", err
+	}
+	defer st.Close()
+	org, err := st.CreateOrg(ctx, "bench")
+	if err != nil {
+		return "", err
+	}
+	team, err := st.CreateTeam(ctx, org, "bench")
+	if err != nil {
+		return "", err
+	}
+	project, err := st.CreateProject(ctx, team, "bench")
+	if err != nil {
+		return "", err
+	}
+	secret, k, err := storepkg.NewKey("key-bench", "bench", project)
+	if err != nil {
+		return "", err
+	}
+	k.CreatedAt = time.Now()
+	return secret, st.CreateKey(ctx, k)
+}
+
+// baselineGuard is the policy init installs, without its judge: the pattern
+// checks every request passes.
+func baselineGuard() (guard.Guard, error) {
+	m, err := config.Parse([]byte(guardSection(false)))
+	if err != nil {
+		return nil, err
+	}
+	cfg, err := config.FromMap(m)
+	if err != nil {
+		return nil, err
+	}
+	return guard.NewGate(cfg.Guard, nil, slog.New(slog.DiscardHandler))
+}

internal/cli/bench_overhead_test.go

@@ -0,0 +1,33 @@
+package cli
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+	"time"
+)
+
+// The short version, so CI sees the gateway's overhead on every change: every
+// mode answers every request, and what the gateway adds is measured, not
+// guessed. No bound is asserted on it, as CI's machines vary; the table is
+// in the test's log.
+func TestTheGatewaysOverheadIsMeasured(t *testing.T) {
+	steps, err := runOverhead(t.Context(), []int{50}, time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(steps) != len(overheadModes) {
+		t.Fatalf("%d steps for %d modes", len(steps), len(overheadModes))
+	}
+	for _, s := range steps {
+		if s.Sent == 0 || s.Failed > 0 || s.P50 <= 0 || s.P99 < s.P50 {
+			t.Errorf("%s: sent %d failed %d p50 %s p99 %s", s.Mode, s.Sent, s.Failed, s.P50, s.P99)
+		}
+	}
+	var b bytes.Buffer
+	printOverhead(&b, steps)
+	if !strings.Contains(b.String(), "gateway+auth+guard") {
+		t.Errorf("table:\n%s", b.String())
+	}
+	t.Logf("\n%s", b.String())
+}

internal/cli/ctl.go

@@ -186,6 +186,7 @@ func newCtlCmd() *cobra.Command {
 		newCapacityCmd(client, &asJSON),
 		newQuotaCmd(client, &asJSON),
 		newGuardCmd(client, &asJSON),
+		newMCPCmd(client, &asJSON),
 		newKBCmd(client, &asJSON),
 		newTrainCmd(client, &asJSON),
 		newConfigCmd(client, &asJSON),
@@ -320,6 +321,8 @@ func locationColumn(n adminapi.NodeView) string {
 // actually served, never what is merely catalogued.
 func modelStatus(m adminapi.ModelView) string {
 	switch {
+	case m.Stopped:
+		return "stopped (llmgw ctl model start)"
 	case m.Parked:
 		return "parked"
 	case m.External != "":

internal/cli/ctl_mcp.go

@@ -0,0 +1,201 @@
+package cli
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
+)
+
+func newMCPCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
+	c := &cobra.Command{
+		Use:   "mcp",
+		Short: "The company's own MCP servers, served through llmgw's /mcp",
+		Long: "An MCP server registered here — Jira, a file server, a database — is served\n" +
+			"through llmgw's /mcp beside llmgw's own tools, its tools named SERVER.tool.\n" +
+			"Its credentials stay on the control planes: a client gives only its llmgw\n" +
+			"key. A key sees and calls only the tools granted it, as patterns, with\n" +
+			"`llmgw keys limits --tools 'jira.*'` at any level of the tenancy tree;\n" +
+			"none granted anywhere is none. Every call is in `llmgw ctl audit`.",
+	}
+	c.AddCommand(newMCPAddCmd(client, asJSON), newMCPListCmd(client, asJSON), newMCPRemoveCmd(client),
+		newMCPTestCmd(client, asJSON))
+	return c
+}
+
+func newMCPAddCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
+	var req adminapi.MCPServerRequest
+	var headers, refs, secretFiles []string
+	var bearerFile string
+	var disabled bool
+	c := &cobra.Command{
+		Use:   "add NAME --url URL",
+		Short: "Register an MCP server, or change one",
+		Example: "  llmgw ctl mcp add jira --url https://jira.internal/mcp --bearer-file /root/jira-token\n" +
+			"  llmgw ctl mcp add llmgw --url llmgw:admin --description \"this cluster, read only\"\n" +
+			"  llmgw ctl mcp add wiki --url https://wiki.internal/mcp --header-ref Authorization=vault:secret/mcp/wiki#token\n" +
+			"  llmgw ctl mcp add jira --disabled      # off, kept",
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			var err error
+			if req.Headers, err = pairs(headers, "--header"); err != nil {
+				return err
+			}
+			if req.HeaderRefs, err = pairs(refs, "--header-ref"); err != nil {
+				return err
+			}
+			files, err := pairs(secretFiles, "--secret-file")
+			if err != nil {
+				return err
+			}
+			// A secret read here and kept in the store, sealed: the file
+			// need not be on every control plane, and is not read again.
+			for header, file := range files {
+				b, err := os.ReadFile(file) //nolint:gosec // a file the operator names
+				if err != nil {
+					return err
+				}
+				if req.Secrets == nil {
+					req.Secrets = map[string]string{}
+				}
+				req.Secrets[header] = strings.TrimSpace(string(b))
+			}
+			if bearerFile != "" {
+				b, err := os.ReadFile(bearerFile) //nolint:gosec // a file the operator names
+				if err != nil {
+					return err
+				}
+				if req.Secrets == nil {
+					req.Secrets = map[string]string{}
+				}
+				req.Secrets["Authorization"] = "Bearer " + strings.TrimSpace(string(b))
+			}
+			if cmd.Flags().Changed("disabled") {
+				on := !disabled
+				req.Enabled = &on
+			}
+			body, _ := json.Marshal(req)
+			var v adminapi.MCPServerView
+			if err := client().put(cmd.Context(), "/api/v1/mcp/servers/"+args[0], body, &v); err != nil {
+				return err
+			}
+			if *asJSON {
+				return json.NewEncoder(cmd.OutOrStdout()).Encode(v)
+			}
+			state := "on"
+			if !v.Enabled {
+				state = "off"
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "%s: %s, %s. Its tools are %s.TOOL in /mcp, to keys granted them "+
+				"(llmgw keys limits --tools '%s.*'). Check it: llmgw ctl mcp test %s\n", v.Name, v.URL, state, v.Name, v.Name, v.Name)
+			return nil
+		},
+	}
+	f := c.Flags()
+	f.StringVar(&req.URL, "url", "", "the server's streamable HTTP address, https://…/mcp; llmgw:admin for this cluster, read only")
+	f.StringVar(&req.Description, "description", "", "what it is, shown beside its tools")
+	f.StringArrayVar(&headers, "header", nil, "NAME=VALUE sent as written, for what is not secret; repeatable")
+	f.StringArrayVar(&refs, "header-ref", nil, "NAME=REF read at each call: a file on every control plane, env:, vault: or store:; repeatable")
+	f.StringArrayVar(&secretFiles, "secret-file", nil, "NAME=FILE read now and kept in the store, sealed: a token; repeatable")
+	f.StringVar(&bearerFile, "bearer-file", "", "a token FILE, read now and kept sealed, sent as Authorization: Bearer")
+	f.BoolVar(&disabled, "disabled", false, "keep it but serve none of its tools")
+	f.IntVar(&req.TimeoutSeconds, "timeout", 0, "seconds one call may take (default 60)")
+	f.IntVar(&req.RatePerMinute, "rate", 0, "calls a minute each caller may make to its tools (default: no bound; -1 takes one away)")
+	return c
+}
+
+func newMCPListCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
+	return &cobra.Command{
+		Use:   "list",
+		Short: "The MCP servers /mcp serves",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			var list []adminapi.MCPServerView
+			if err := client().get(cmd.Context(), "/api/v1/mcp/servers", &list); err != nil {
+				return err
+			}
+			if *asJSON {
+				return json.NewEncoder(cmd.OutOrStdout()).Encode(list)
+			}
+			if len(list) == 0 {
+				fmt.Fprintln(cmd.OutOrStdout(), "no MCP servers; add one: llmgw ctl mcp add NAME --url URL")
+				return nil
+			}
+			w := tabTo(cmd.OutOrStdout())
+			fmt.Fprintln(w, "NAME\tSTATE\tURL\tCREDENTIALS\tDESCRIPTION")
+			for _, s := range list {
+				state := "on"
+				if !s.Enabled {
+					state = "off"
+				}
+				var creds []string
+				for h := range s.HeaderRefs {
+					creds = append(creds, h)
+				}
+				fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", s.Name, state, s.URL, dash(strings.Join(creds, ",")), s.Description)
+			}
+			return w.Flush()
+		},
+	}
+}
+
+func newMCPRemoveCmd(client func() *ctlClient) *cobra.Command {
+	return &cobra.Command{
+		Use:   "remove NAME",
+		Short: "Remove an MCP server: its tools leave /mcp",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if err := client().delete(cmd.Context(), "/api/v1/mcp/servers/"+args[0], nil); err != nil {
+				return err
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "%s removed; its tools leave /mcp within half a minute\n", args[0])
+			return nil
+		},
+	}
+}
+
+func newMCPTestCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
+	return &cobra.Command{
+		Use:   "test NAME",
+		Short: "Ask an MCP server for its tools, with its credentials, as /mcp would",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			var v adminapi.MCPTestView
+			if err := client().post(cmd.Context(), "/api/v1/mcp/servers/"+args[0]+"/test", nil, &v); err != nil {
+				return err
+			}
+			if *asJSON {
+				return json.NewEncoder(cmd.OutOrStdout()).Encode(v)
+			}
+			if !v.OK {
+				return errors.New(args[0] + " did not answer: " + v.Error)
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "%s answers with %d tool(s):\n", args[0], len(v.Tools))
+			for _, t := range v.Tools {
+				fmt.Fprintln(cmd.OutOrStdout(), "  "+t)
+			}
+			return nil
+		},
+	}
+}
+
+// pairs reads NAME=VALUE flags.
+func pairs(list []string, flag string) (map[string]string, error) {
+	if len(list) == 0 {
+		return nil, nil
+	}
+	out := map[string]string{}
+	for _, p := range list {
+		k, v, ok := strings.Cut(p, "=")
+		if !ok || strings.TrimSpace(k) == "" {
+			return nil, fmt.Errorf("%s %q is not NAME=VALUE", flag, p)
+		}
+		out[strings.TrimSpace(k)] = v
+	}
+	return out, nil
+}

internal/cli/ctl_upgrade.go

@@ -11,11 +11,13 @@ import (
 	"runtime"
 	"slices"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/spf13/cobra"
 
 	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/control/agentsvc"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/onboard"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/release"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/version"
@@ -244,6 +246,7 @@ func upgradeNodes(ctx context.Context, out io.Writer, client func() *ctlClient,
 	}
 	slices.SortFunc(nodes, func(a, b adminapi.NodeView) int { return strings.Compare(a.ID, b.ID) })
 	var todo []adminapi.NodeView
+	var away []string
 	skipped := 0
 	for _, n := range nodes {
 		if len(only) > 0 && !slices.Contains(only, n.ID) {
@@ -253,8 +256,17 @@ func upgradeNodes(ctx context.Context, out io.Writer, client func() *ctlClient,
 			skipped++
 			continue
 		}
+		// A node that is not connected cannot be told, and one tried first
+		// stopped every run at it: passed over, and named at the end.
+		if n.State == "lost" || n.State == "unreachable" {
+			away = append(away, n.ID)
+			continue
+		}
 		todo = append(todo, n)
 	}
+	if len(away) > 0 {
+		fmt.Fprintf(out, "Passed over, not connected: %s\n", strings.Join(away, ", "))
+	}
 	parallel = max(parallel, 1)
 	start, size, done := time.Now(), 1, 0
 	for len(todo) > 0 {
@@ -296,7 +308,10 @@ func upgradeNodes(ctx context.Context, out io.Writer, client func() *ctlClient,
 }
 
 // upgradeWave tells every node in the wave at once, and waits until each is
-// back on v, ready, with as many ready replicas as it had.
+// back on v and serving what it served.
+//
+// Told together, not one after another: each answer can take minutes, and a
+// wave of twenty waited for them in turn with nothing on the screen.
 func upgradeWave(ctx context.Context, out io.Writer, client func() *ctlClient, v string,
 	wave []adminapi.NodeView, perNode time.Duration,
 ) error {
@@ -308,35 +323,61 @@ func upgradeWave(ctx context.Context, out io.Writer, client func() *ctlClient, v
 	}
 	fmt.Fprintf(out, "== %d node(s): %s\n", len(wave), abbreviate(ids, 8))
 	body, _ := json.Marshal(adminapi.UpgradeRequest{Version: v})
-	var failed []string
+	var (
+		mu     sync.Mutex
+		failed []string
+		wg     sync.WaitGroup
+	)
 	for _, n := range wave {
-		// The control plane waits for the agent to fetch and check the
-		// release, up to five minutes; fifteen seconds gave up on a node
-		// that was upgrading.
-		if err := client().patient(6*time.Minute).post(ctx, "/api/v1/nodes/"+n.ID+"/upgrade", body, nil); err != nil {
-			failed = append(failed, fmt.Sprintf("%s: %v", n.ID, err))
-		}
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			// The control plane waits for the agent's answer, or for it to
+			// come back on v, longer than the agent gives its download.
+			err := client().patient(agentsvc.UpgradeWait+time.Minute).post(ctx, "/api/v1/nodes/"+n.ID+"/upgrade", body, nil)
+			mu.Lock()
+			defer mu.Unlock()
+			if err != nil {
+				failed = append(failed, fmt.Sprintf("%s: %v", n.ID, err))
+				fmt.Fprintf(out, "   %s: not upgraded: %v\n", n.ID, err)
+				return
+			}
+			fmt.Fprintf(out, "   %s: on %s, coming back\n", n.ID, v)
+		}()
 	}
-	if len(failed) > 0 {
-		return fmt.Errorf("not told to upgrade:\n  %s\n`llmgw ctl logs NODE` says more", strings.Join(failed, "\n  "))
-	}
-	waiting := slices.Clone(ids)
+	wg.Wait()
+	waiting := slices.DeleteFunc(slices.Clone(ids), func(id string) bool {
+		return slices.ContainsFunc(failed, func(f string) bool { return strings.HasPrefix(f, id+": ") })
+	})
 	deadline := time.Now().Add(perNode)
-	for {
+	backAt := map[string]time.Time{}
+	said := time.Now()
+	for len(waiting) > 0 {
 		var now []adminapi.NodeView
 		_ = client().get(ctx, "/api/v1/nodes", &now)
-		after := readyReplicasByNode(ctx, client)
+		var reps []adminapi.ReplicaView
+		_ = client().get(ctx, "/api/v1/replicas", &reps)
+		after, starting := replicasByNode(reps)
 		state := map[string]adminapi.NodeView{}
 		for _, x := range now {
 			state[x.ID] = x
 		}
 		waiting = slices.DeleteFunc(waiting, func(id string) bool {
 			cur := state[id]
-			return cur.AgentVersion == v && cur.State == "ready" && after[id] >= before[id]
+			// Connected and on v: ready, or cordoned or draining as it
+			// was, which an upgrade does not undo.
+			if cur.AgentVersion != v || (cur.State != "ready" && cur.State != "cordoned" && cur.State != "draining") {
+				return false
+			}
+			if _, ok := backAt[id]; !ok {
+				backAt[id] = time.Now()
+			}
+			// Serving what it served; or, a while on, nothing on it still
+			// starting: a model that went idle meanwhile is not one lost.
+			return after[id] >= before[id] || (time.Since(backAt[id]) > 90*time.Second && starting[id] == 0)
 		})
 		if len(waiting) == 0 {
-			fmt.Fprintf(out, "   done in %s\n", time.Since(start).Round(time.Second))
-			return nil
+			break
 		}
 		if time.Now().After(deadline) {
 			var why []string
@@ -345,11 +386,49 @@ func upgradeWave(ctx context.Context, out io.Writer, client func() *ctlClient, v
 				why = append(why, fmt.Sprintf("%s (version %q, state %q, replicas %d/%d)",
 					id, cur.AgentVersion, cur.State, after[id], before[id]))
 			}
-			return fmt.Errorf("not back within %s:\n  %s\n`llmgw ctl logs NODE` says why, and each keeps its "+
-				"previous binary beside the new one", perNode, strings.Join(why, "\n  "))
+			failed = append(failed, fmt.Sprintf("not back within %s: %s", perNode, strings.Join(why, ", ")))
+			break
+		}
+		if time.Since(said) >= 30*time.Second {
+			var w []string
+			for _, id := range waiting {
+				cur := state[id]
+				w = append(w, fmt.Sprintf("%s (%s, %s, replicas %d/%d)", id, orUnknown(cur.AgentVersion), cur.State,
+					after[id], before[id]))
+			}
+			fmt.Fprintf(out, "   waiting for %s\n", abbreviate(w, 8))
+			said = time.Now()
 		}
 		time.Sleep(2 * time.Second)
 	}
+	if len(failed) > 0 {
+		return fmt.Errorf("not upgraded:\n  %s\n`llmgw ctl logs NODE` says why; each keeps its previous binary beside the new one",
+			strings.Join(failed, "\n  "))
+	}
+	fmt.Fprintf(out, "   done in %s\n", time.Since(start).Round(time.Second))
+	return nil
+}
+
+// replicasByNode counts each node's ready replicas, and those still placing
+// or starting.
+func replicasByNode(reps []adminapi.ReplicaView) (ready, starting map[string]int) {
+	ready, starting = map[string]int{}, map[string]int{}
+	for _, r := range reps {
+		seen := map[string]bool{}
+		for _, sh := range r.Shards {
+			if seen[sh.Node] {
+				continue
+			}
+			seen[sh.Node] = true
+			switch r.State {
+			case "ready":
+				ready[sh.Node]++
+			case "placing", "starting":
+				starting[sh.Node]++
+			}
+		}
+	}
+	return ready, starting
 }
 
 // abbreviate lists up to n names, and says how many more.

internal/cli/ctl_upgrade_test.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"slices"
 	"strings"
 	"sync"
 	"testing"
@@ -21,6 +22,8 @@ type fakeFleet struct {
 	versions map[string]string
 	stuck    map[string]bool
 	told     []string
+	// states are nodes' states other than ready.
+	states map[string]string
 }
 
 func (f *fakeFleet) server(t *testing.T) *httptest.Server {
@@ -31,7 +34,11 @@ func (f *fakeFleet) server(t *testing.T) *httptest.Server {
 		case r.URL.Path == "/api/v1/nodes":
 			var out []adminapi.NodeView
 			for id, v := range f.versions {
-				out = append(out, adminapi.NodeView{ID: id, State: "ready", AgentVersion: v})
+				st := "ready"
+				if f.states[id] != "" {
+					st = f.states[id]
+				}
+				out = append(out, adminapi.NodeView{ID: id, State: st, AgentVersion: v})
 			}
 			_ = json.NewEncoder(w).Encode(out)
 		case r.URL.Path == "/api/v1/replicas":
@@ -201,3 +208,23 @@ func TestUpgradingAControlPlaneAloneSaysItsNodesWereNot(t *testing.T) {
 		t.Errorf("said something with every node on the version: %s", out.String())
 	}
 }
+
+// A cordoned node upgraded is done, as it was; a node not connected is passed
+// over rather than stopping every node after it.
+func TestAnUpgradeTakesACordonedNodeAndPassesOverOneAway(t *testing.T) {
+	f := &fakeFleet{versions: map[string]string{"a": "v1.0.0", "b": "v1.0.0", "c": "v1.0.0"},
+		states: map[string]string{"a": "lost", "b": "cordoned"}}
+	srv := f.server(t)
+	var out bytes.Buffer
+	err := upgradeNodes(t.Context(), &out, func() *ctlClient { return newCtlClient(srv.URL) }, "v1.0.1", nil, 5*time.Second, 2)
+	if slices.Contains(f.told, "a") || !slices.Contains(f.told, "b") || !slices.Contains(f.told, "c") {
+		t.Errorf("told %v", f.told)
+	}
+	if !strings.Contains(out.String(), "Passed over, not connected: a") {
+		t.Errorf("output:\n%s", out.String())
+	}
+	// The one away is named at the end, behind.
+	if err == nil || !strings.Contains(err.Error(), "a (v1.0.0, lost)") {
+		t.Errorf("err %v", err)
+	}
+}

internal/cli/guard_judge.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -33,7 +34,7 @@ func newGuardJudgeCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
 			"then fetches and serves by itself: " + knownJudgeNames() + ".",
 	}
 	c.AddCommand(newGuardJudgeStatusCmd(client, asJSON), newGuardJudgeEnableCmd(client),
-		newGuardJudgeUseCmd(client), newGuardJudgeAskCmd(client, asJSON))
+		newGuardJudgeUseCmd(client), newGuardJudgeAskCmd(client, asJSON), newGuardJudgeCheckCmd(client, asJSON))
 	return c
 }
 
@@ -383,3 +384,70 @@ func newGuardJudgeAskCmd(client func() *ctlClient, asJSON *bool) *cobra.Command
 	c.Flags().StringVar(&answer, "answer", "", "an assistant's reply to TEXT, judged as output is")
 	return c
 }
+
+func newGuardJudgeCheckCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
+	var model string
+	var burst int
+	c := &cobra.Command{
+		Use:   "check",
+		Short: "How a judge keeps up: a judgment alone and among others, against the time a request waits",
+		Long: "Times three judgments of a prompt of about 280 tokens, one after another, then\n" +
+			"a burst of them at once (two for each ready replica unless --burst says),\n" +
+			"and sets both against the policies' latency budget. A judgment past the\n" +
+			"budget is refused under fail: closed; past half of it alone, or past it\n" +
+			"among others, a busy moment refuses requests. Each request is judged once\n" +
+			"for its prompt and again every 600 characters of its answer.",
+		Args: cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			v, err := checkJudge(cmd.Context(), client(), model, burst)
+			if err != nil {
+				return err
+			}
+			if *asJSON {
+				return emitJSON(v)
+			}
+			fmt.Fprint(cmd.OutOrStdout(), judgeCheckText(v))
+			return nil
+		},
+	}
+	c.Flags().StringVar(&model, "model", "", "the judge (default: the one the policies ask)")
+	c.Flags().IntVar(&burst, "burst", 0, "judgments at once (default: two for each ready replica)")
+	return c
+}
+
+func checkJudge(ctx context.Context, c *ctlClient, model string, burst int) (adminapi.JudgeCheckView, error) {
+	body, _ := json.Marshal(adminapi.JudgeCheckRequest{Model: model, Burst: burst})
+	var v adminapi.JudgeCheckView
+	err := c.patient(3*time.Minute).post(ctx, "/api/v1/guard/judges/check", body, &v)
+	return v, err
+}
+
+// judgeCheckText says a check in a few lines, and what to do when it is not
+// fine.
+func judgeCheckText(v adminapi.JudgeCheckView) string {
+	var b strings.Builder
+	took := make([]string, len(v.TookMs))
+	for i, t := range v.TookMs {
+		took[i] = fmt.Sprintf("%.1f", float64(t)/1000)
+	}
+	fmt.Fprintf(&b, "%s, %d replica(s) ready, a request waits %.1f s for it\n", v.Model, v.Ready, float64(v.BudgetMs)/1000)
+	fmt.Fprintf(&b, "  alone:    %s s\n", strings.Join(took, ", "))
+	fmt.Fprintf(&b, "  %d at once: slowest %.1f s", v.Burst, float64(v.BurstSlowestMs)/1000)
+	if v.BurstFailed > 0 {
+		fmt.Fprintf(&b, ", %d gave no verdict", v.BurstFailed)
+	}
+	fmt.Fprintf(&b, "; about %.1f judgments a second, so about %.1f requests a second with short answers\n",
+		v.PerSecond, v.PerSecond/2)
+	switch v.Verdict {
+	case "ok":
+		b.WriteString("ok: well inside the budget\n")
+	case "tight":
+		b.WriteString("tight: a busy moment passes the budget\n")
+	default:
+		b.WriteString("slow: a judgment alone passes the budget\n")
+	}
+	for _, a := range v.Advice {
+		b.WriteString("  - " + a + "\n")
+	}
+	return b.String()
+}

internal/cli/judgekeeper.go

@@ -32,12 +32,34 @@ type judgeKeeper struct {
 	// tried is when each judge was last asked for, so one that cannot be
 	// fetched is not asked for again on every look.
 	tried map[string]time.Time
+	// grace is how long after its first look the keeper serves no judge
+	// itself: init adds its own judge just after the control plane starts,
+	// sized and placed as the install says, and one the leader added first
+	// was what init then kept. Zero waits for nothing.
+	grace time.Duration
+	first time.Time
+
+	// What refitting an earlier install's judge needs: the catalog to change
+	// its profile in, the replicas to restart, and the nodes' CPUs. Any nil
+	// leaves judges as they are.
+	profiles interface {
+		SetProfiles(ctx context.Context, name string, profiles []catalog.Profile, by string) (catalog.Model, error)
+	}
+	restart  func(ids ...string) error
+	replicas func(model string) []string
+	nodeCPUs func() []int
+	// looked is each judge already refitted or found changed by hand, so
+	// each is said once.
+	looked map[string]bool
 }
 
 // judgeRetry is how long a judge whose serving failed waits before it is
 // asked for again.
 const judgeRetry = 10 * time.Minute
 
+// judgeGrace is the keeper's grace on a control plane just started.
+const judgeGrace = 10 * time.Minute
+
 func (k *judgeKeeper) run(ctx context.Context, every time.Duration) {
 	t := time.NewTicker(every)
 	defer t.Stop()
@@ -69,6 +91,13 @@ func (k *judgeKeeper) check() {
 	have := map[string]bool{}
 	for _, m := range k.models() {
 		have[m.Name] = true
+		k.refit(m)
+	}
+	if k.first.IsZero() {
+		k.first = now()
+	}
+	if now().Sub(k.first) < k.grace {
+		return
 	}
 	busy := map[string]bool{}
 	for _, j := range k.serve.Jobs() {
@@ -96,6 +125,15 @@ func (k *judgeKeeper) check() {
 		}
 		k.tried[name] = now()
 		var opts judgeServeOptions
+		if !kj.GPU {
+			// The cores init would give the same number of judges.
+			var cpus []int
+			if k.nodeCPUs != nil {
+				cpus = k.nodeCPUs()
+			}
+			opts.Replicas = 2
+			opts.Cores = refitCores(opts.Replicas, cpus)
+		}
 		if kj.GPU {
 			if opts.GPUClass = roomiestGPUClass(k.gpus()); opts.GPUClass == "" {
 				k.log.Warn("a policy names a judge that runs on a GPU, and this cluster has none",
@@ -105,6 +143,8 @@ func (k *judgeKeeper) check() {
 		}
 		req := kj.serveRequest(opts)
 		req.By = "llmgw (a guard policy names it)"
+		// init, or an operator, may add it while this fetches: theirs stays.
+		req.IfAbsent = true
 		job, err := k.serve.Start(req)
 		if err != nil {
 			k.log.Error("could not start serving a judge a policy names", "judge", name, "err", err)
@@ -114,3 +154,88 @@ func (k *judgeKeeper) check() {
 			"judge", name, "repo", kj.Repo, "file", kj.File, "job", job.ID)
 	}
 }
+
+// refit moves a judge an earlier `server init` installed to what init
+// installs now, and restarts its replicas onto it. Those judges reserved no
+// cores or one, 2 or 4 GB, and ran llama.cpp's prompt cache: on fewer than
+// eight cores every judgment missed its 5 s budget and fail: closed refused
+// every request, until fixed by hand. A judge whose profile differs in any
+// other way was set by somebody, and is left as it is, said once.
+func (k *judgeKeeper) refit(m catalog.Model) {
+	if k.profiles == nil || k.restart == nil || k.replicas == nil || m.Name != defaultJudge || !m.IsGuard() {
+		return
+	}
+	if k.looked == nil {
+		k.looked = map[string]bool{}
+	}
+	if k.looked[m.Name] {
+		return
+	}
+	k.looked[m.Name] = true
+	if !earlierInitJudge(m) {
+		if len(m.Profiles) != 1 || !slices.Contains(m.Profiles[0].Args, "--cache-ram") {
+			k.log.Info("the judge's profile is not one init wrote; left as it is",
+				"judge", m.Name, "see", "llmgw ctl model resources "+m.Name)
+		}
+		return
+	}
+	var cpus []int
+	if k.nodeCPUs != nil {
+		cpus = k.nodeCPUs()
+	}
+	p := m.Profiles[0]
+	p.MinMemoryGB = judgeMemoryGB
+	p.CPUCores = refitCores(m.Scaling.Min, cpus)
+	p.Args = []string{"--ctx-size", "8192", "--cache-ram", "0"}
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	if _, err := k.profiles.SetProfiles(ctx, m.Name, []catalog.Profile{p}, "llmgw (the judge an earlier init installed)"); err != nil {
+		k.log.Warn("could not refit the judge an earlier init installed", "judge", m.Name, "err", err)
+		k.looked[m.Name] = false
+		return
+	}
+	ids := k.replicas(m.Name)
+	if len(ids) > 0 {
+		if err := k.restart(ids...); err != nil {
+			k.log.Warn("refitted the judge, but could not restart it", "judge", m.Name, "err", err)
+		}
+	}
+	k.log.Info("refitted the judge an earlier init installed", "judge", m.Name,
+		"memory_gb", p.MinMemoryGB, "cpu_cores", p.CPUCores, "replicas_restarted", len(ids))
+}
+
+// earlierInitJudge is whether a judge's entry is exactly what `server init`
+// before v0.14.7 wrote: one llama.cpp profile on CPUs, an 8192 context and
+// no other args, 2 or 4 GB, none to two cores.
+func earlierInitJudge(m catalog.Model) bool {
+	if len(m.Profiles) != 1 {
+		return false
+	}
+	p := m.Profiles[0]
+	return p.Name == "cpu" && p.Engine == "llamacpp" && p.GPUClass == "" && p.GPU == nil &&
+		len(p.NodeSelector) == 0 && slices.Equal(p.Args, []string{"--ctx-size", "8192"}) &&
+		(p.MinMemoryGB == 2 || p.MinMemoryGB == 4) && p.CPUCores >= 0 && p.CPUCores <= 2
+}
+
+// refitCores is a judge replica's cores by init's rule: up to four for the
+// one judge of a cluster, two each where there are more, fewer where the
+// smallest node cannot hold them all.
+func refitCores(replicas int, cpus []int) int {
+	smallest := 0
+	for _, c := range cpus {
+		if c > 0 && (smallest == 0 || c < smallest) {
+			smallest = c
+		}
+	}
+	if replicas <= 1 {
+		if smallest == 0 {
+			return judgeCores
+		}
+		return min(smallest, judgeCoresAlone)
+	}
+	cores := judgeCores
+	if len(cpus) == 1 && smallest > 0 && replicas*cores > smallest {
+		cores = max(1, smallest/replicas)
+	}
+	return cores
+}

internal/cli/judgekeeper_test.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"context"
 	"errors"
 	"log/slog"
 	"slices"
@@ -51,7 +52,8 @@ func TestAJudgeAPolicyNamesIsFetchedWhenTheCatalogLacksIt(t *testing.T) {
 	// The GPU judge alone: the CPU one is there, and one llmgw does not know
 	// is not guessed at.
 	if len(fs.started) != 1 || fs.started[0].Name != "qwen3guard-4b" || fs.started[0].GPUClass != "6000-24g" ||
-		fs.started[0].Class != catalog.ClassStandard || fs.started[0].GuardFormat != "qwen3guard" || fs.started[0].CPU {
+		fs.started[0].Class != catalog.ClassStandard || fs.started[0].GuardFormat != "qwen3guard" || fs.started[0].CPU ||
+		!fs.started[0].IfAbsent {
 		t.Fatalf("started %+v", fs.started)
 	}
 
@@ -90,8 +92,12 @@ func TestAJudgeAPolicyNamesIsFetchedWhenTheCatalogLacksIt(t *testing.T) {
 	lib = guard.Config{Policies: map[string]guard.Policy{"b": {Judge: &guard.JudgePolicy{Model: "qwen3guard-0.6b", Input: "block"}}}}
 	inCatalog = nil
 	k.gpus = func() []adminapi.ClassUse { return nil }
+	k.nodeCPUs = func() []int { return []int{8, 4} }
 	k.check()
-	if last := fs.started[len(fs.started)-1]; last.Name != "qwen3guard-0.6b" || !last.CPU || last.Replicas != 2 {
+	// Sized as init sizes its two judges: 2 GB, and two cores each on a
+	// cluster whose smallest node has four.
+	if last := fs.started[len(fs.started)-1]; last.Name != "qwen3guard-0.6b" || !last.CPU || last.Replicas != 2 ||
+		last.MemoryGB != judgeMemoryGB || last.CPUCores != refitCores(2, []int{8, 4}) || last.CPUCores == 0 {
 		t.Errorf("CPU judge: %+v", last)
 	}
 	fs.err = errors.New("the mirror is down")
@@ -124,3 +130,108 @@ func TestCategoriesFollowTheJudges(t *testing.T) {
 		t.Errorf("no categories (every one counts) became %v", got)
 	}
 }
+
+type fakeProfiles struct {
+	set map[string][]catalog.Profile
+}
+
+func (f *fakeProfiles) SetProfiles(_ context.Context, name string, ps []catalog.Profile, _ string) (catalog.Model, error) {
+	if f.set == nil {
+		f.set = map[string][]catalog.Profile{}
+	}
+	f.set[name] = ps
+	return catalog.Model{Name: name, Profiles: ps}, nil
+}
+
+// A judge that v0.14.6 or earlier's init installed is moved to today's
+// figures, once, and its replicas restarted onto them; one somebody changed
+// is left alone.
+func TestAnEarlierInstallsJudgeIsRefittedOnce(t *testing.T) {
+	lib := guard.Config{Policies: map[string]guard.Policy{
+		"baseline": {Judge: &guard.JudgePolicy{Model: "qwen3guard-0.6b", Input: "block"}},
+	}}
+	earlier := guardModel("http://10.0.0.5:8081/qwen3guard-0.6b/guard/g.gguf", 2, 1, nil)
+	earlier.Profiles[0].MinMemoryGB, earlier.Profiles[0].Args = 4, []string{"--ctx-size", "8192"}
+	inCatalog := []catalog.Model{earlier}
+	fp := &fakeProfiles{}
+	var restarted []string
+	k := &judgeKeeper{
+		library:  func() guard.Config { return lib },
+		models:   func() []catalog.Model { return inCatalog },
+		serve:    &fakeServe{},
+		log:      slog.New(slog.DiscardHandler),
+		profiles: fp,
+		restart:  func(ids ...string) error { restarted = append(restarted, ids...); return nil },
+		replicas: func(string) []string { return []string{"j-1", "j-2"} },
+		nodeCPUs: func() []int { return []int{4} },
+	}
+	k.check()
+	got := fp.set["qwen3guard-0.6b"]
+	if len(got) != 1 || got[0].MinMemoryGB != 2 || got[0].CPUCores != 2 || !slices.Contains(got[0].Args, "--cache-ram") {
+		t.Fatalf("refitted to %+v", got)
+	}
+	if !slices.Equal(restarted, []string{"j-1", "j-2"}) {
+		t.Errorf("restarted %v", restarted)
+	}
+	k.check()
+	if len(restarted) != 2 {
+		t.Error("refitted twice")
+	}
+
+	// Changed by somebody: an extra arg. Left as it is.
+	mine := guardModel("http://x/g.gguf", 2, 3, nil)
+	mine.Profiles[0].Args = []string{"--ctx-size", "16384"}
+	inCatalog = []catalog.Model{mine}
+	fp.set, k.looked = nil, nil
+	k.check()
+	if fp.set != nil {
+		t.Errorf("a judge set by hand was changed: %+v", fp.set)
+	}
+}
+
+func TestAJudgeIsRefittedToTheCoresInitWouldGive(t *testing.T) {
+	for _, c := range []struct {
+		replicas int
+		cpus     []int
+		want     int
+	}{
+		{1, []int{4}, 4},
+		{1, []int{2}, 2},
+		{1, []int{16}, 4},
+		{2, []int{4}, 2},
+		{2, []int{2}, 1},
+		{2, []int{4, 32}, 2},
+		{2, nil, 2},
+	} {
+		if got := refitCores(c.replicas, c.cpus); got != c.want {
+			t.Errorf("%d judges on %v: %d cores, want %d", c.replicas, c.cpus, got, c.want)
+		}
+	}
+}
+
+// Just after the control plane starts, the judge init is adding is left to
+// init: the keeper serves one itself only after its grace.
+func TestTheKeeperLeavesAJustStartedInstallsJudgeToInit(t *testing.T) {
+	lib := guard.Config{Policies: map[string]guard.Policy{"b": {Judge: &guard.JudgePolicy{Model: "qwen3guard-0.6b", Input: "block"}}}}
+	now := time.Date(2026, 10, 19, 12, 0, 0, 0, time.UTC)
+	fs := &fakeServe{}
+	k := &judgeKeeper{
+		library: func() guard.Config { return lib },
+		models:  func() []catalog.Model { return nil },
+		serve:   fs, grace: judgeGrace,
+		gpus: func() []adminapi.ClassUse { return nil },
+		log:  slog.New(slog.DiscardHandler),
+		now:  func() time.Time { return now },
+	}
+	k.check()
+	now = now.Add(judgeGrace / 2)
+	k.check()
+	if len(fs.started) != 0 {
+		t.Fatalf("served within its grace: %+v", fs.started)
+	}
+	now = now.Add(judgeGrace)
+	k.check()
+	if len(fs.started) != 1 {
+		t.Errorf("never served after its grace: %d", len(fs.started))
+	}
+}

internal/cli/judges_known.go

@@ -142,7 +142,9 @@ func (k knownJudge) serveRequest(o judgeServeOptions) modelserve.Request {
 		}
 		return req
 	}
-	req.CPU, req.CPUCores = true, o.Cores
+	// Sized as init sizes its judge: the memory it measured to need with
+	// no prompt cache, and the cores its rule gives.
+	req.CPU, req.CPUCores, req.MemoryGB = true, o.Cores, judgeMemoryGB
 	if req.Replicas == 0 {
 		req.Replicas = 2
 	}

internal/cli/keys.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"path"
 	"slices"
 	"strings"
 	"text/tabwriter"
@@ -301,7 +302,8 @@ func newLimitsCmd(open opener) *cobra.Command {
 	var perMember bool
 	var rpm, tpm int
 	var budget float64
-	var models []string
+	var models, tools []string
+	var replace bool
 
 	cmd := &cobra.Command{
 		Use:   "limits",
@@ -357,7 +359,19 @@ func newLimitsCmd(open opener) *cobra.Command {
 					return errors.New("--per-member is for --scope org, team or project")
 				}
 			}
+			// Only what is given changes: setting a tool grant must not
+			// clear the scope's rate or budget. --replace writes the row
+			// whole, a flag not given then no limit, as the console's
+			// form does with every field it shows.
 			l := store.Limits{Scope: level, ScopeID: scopeID}
+			if !replace {
+				switch cur, err := s.LimitsFor(cmd.Context(), level, scopeID); {
+				case err == nil:
+					l = cur
+				case !errors.Is(err, store.ErrNotFound):
+					return err
+				}
+			}
 			if cmd.Flags().Changed("rpm") {
 				l.RPM = &rpm
 			}
@@ -379,6 +393,14 @@ func newLimitsCmd(open opener) *cobra.Command {
 				}
 				l.AllowedModels = models
 			}
+			if cmd.Flags().Changed("tools") {
+				for _, p := range tools {
+					if _, err := path.Match(p, "x.y"); err != nil {
+						return fmt.Errorf("--tools %q is not a pattern: %w", p, err)
+					}
+				}
+				l.AllowedTools = tools
+			}
 			if err := s.PutLimits(cmd.Context(), l); err != nil {
 				return err
 			}
@@ -395,6 +417,10 @@ func newLimitsCmd(open opener) *cobra.Command {
 	cmd.Flags().Float64Var(&budget, "budget", 0, "budget per period, in whole units as the quotas page shows them")
 	cmd.Flags().StringVar(&period, "period", "month", "day | month")
 	cmd.Flags().StringSliceVar(&models, "models", nil, "allowed models; empty allows none")
+	cmd.Flags().BoolVar(&replace, "replace", false,
+		"write every limit at the scope: one not given is then no limit there (default: only what is given changes)")
+	cmd.Flags().StringSliceVar(&tools, "tools", nil,
+		"the company MCP servers' tools granted here, as patterns: jira.*,db.query; none granted anywhere is none")
 	return cmd
 }
 

internal/cli/leaderforward.go

@@ -73,8 +73,10 @@ func (f *leaderForward) standby(next http.Handler) http.Handler {
 		p := &httputil.ReverseProxy{
 			Rewrite: func(pr *httputil.ProxyRequest) {
 				pr.Out.URL.Scheme, pr.Out.URL.Host = "https", target.Host
+				// Escaped as it came: a name with a slash in it, Demo/hr
+				// as Demo%2Fhr, is one segment, not two.
 				pr.Out.URL.Path = forwardPrefix + pr.In.URL.Path
-				pr.Out.URL.RawPath = ""
+				pr.Out.URL.RawPath = forwardPrefix + pr.In.URL.EscapedPath()
 				pr.Out.Host = target.Host
 				// The leader's own token is not this one's, and the
 				// certificate is what it believes.
@@ -221,7 +223,7 @@ func (f *leaderForward) leaderSide(admin http.Handler) http.Handler {
 			return
 		}
 		r2 := r.Clone(r.Context())
-		r2.URL.Path, r2.URL.RawPath = path, ""
+		r2.URL.Path, r2.URL.RawPath = path, strings.TrimPrefix(r.URL.EscapedPath(), forwardPrefix)
 		w.Header().Set(hdrAnsweredBy, f.self)
 		admin.ServeHTTP(w, r2)
 	})

internal/cli/leaderforward_test.go

@@ -77,7 +77,7 @@ func newForwardCluster(t *testing.T) *forwardCluster {
 
 	// The leader's admin API: says whose it is, and who it was asked by.
 	admin := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		_ = json.NewEncoder(w).Encode(map[string]string{"path": r.URL.Path, "by": r.Header.Get(hdrForwardedBy),
+		_ = json.NewEncoder(w).Encode(map[string]string{"path": r.URL.Path, "raw": r.URL.EscapedPath(), "by": r.Header.Get(hdrForwardedBy),
 			"auth": r.Header.Get("Authorization"), "actor": r.Header.Get("X-Llmgw-Actor")})
 	})
 	mux := http.NewServeMux()
@@ -242,3 +242,13 @@ func TestAStandbysPortalIsTheLeaders(t *testing.T) {
 		t.Errorf("a forwarded request was forwarded again: %q", body)
 	}
 }
+
+// A name with a slash in it, escaped, stays one segment on the leader: a
+// collection Demo/hr removed through a standby was a 405 there.
+func TestAnEscapedSlashReachesTheLeaderEscaped(t *testing.T) {
+	c := newForwardCluster(t)
+	resp, got := c.ask(t, "/api/v1/kb/collections/Demo%2Fhr")
+	if resp.StatusCode != http.StatusOK || got["raw"] != "/api/v1/kb/collections/Demo%2Fhr" {
+		t.Fatalf("%d %v", resp.StatusCode, got)
+	}
+}

internal/cli/mirror.go

@@ -16,6 +16,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/hf"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/mirror"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/tlsconf"
 )
@@ -51,12 +52,13 @@ func newMirrorCmd() *cobra.Command {
 		newMirrorRemoveCmd(&dir),
 		newMirrorServeCmd(&dir),
 		newMirrorInitCmd(&dir),
+		newMirrorAddPeerCmd(&dir),
 	)
 	return c
 }
 
 func newMirrorAddCmd(dir *string) *cobra.Command {
-	var model, version, as string
+	var model, version, as, sha, registry string
 
 	c := &cobra.Command{
 		Use:   "add <url>...",
@@ -78,7 +80,7 @@ func newMirrorAddCmd(dir *string) *cobra.Command {
 			if model == "" || version == "" {
 				return fmt.Errorf("--model and --version are required: they are the layout")
 			}
-			if as != "" && len(args) > 1 {
+			if (as != "" || sha != "") && len(args) > 1 {
 				return fmt.Errorf("--as names one file; with %d URLs each keeps its own name", len(args))
 			}
 			out := cmd.OutOrStdout()
@@ -89,6 +91,21 @@ func newMirrorAddCmd(dir *string) *cobra.Command {
 					file = mirror.LastPathElement(source)
 				}
 				e := mirror.Entry{Model: model, Version: version, File: file}
+				// From the registry: what it published for the file, to
+				// compare with what arrives.
+				want := strings.ToLower(sha)
+				if id, rev, path, ok := hf.FileSource(source, registry); ok && want == "" {
+					repo, err := hf.New(registry, 30*time.Second).RepoAt(cmd.Context(), id, rev)
+					if err != nil {
+						return fmt.Errorf("looking up %s in the registry, for the sha256 it published: %w "+
+							"(--sha256 gives it instead)", id, err)
+					}
+					for _, f := range repo.Files {
+						if f.Path == path {
+							want = f.SHA256
+						}
+					}
+				}
 				fmt.Fprintf(out, "fetching %s\n", source)
 				added, err := mirror.Add(cmd.Context(), *dir, source, e, func(done, total int64) {
 					if total > 0 {
@@ -101,6 +118,14 @@ func newMirrorAddCmd(dir *string) *cobra.Command {
 				if err != nil {
 					return err
 				}
+				if want != "" && added.SHA256 != want {
+					_ = mirror.Remove(*dir, e)
+					return fmt.Errorf("%s arrived with sha256 %s, and %s was published for it: deleted",
+						source, added.SHA256, want)
+				}
+				if want != "" {
+					fmt.Fprintln(out, "  sha256 matches the one published")
+				}
 				fmt.Fprintf(out, "%s/%s/%s  %s\n  sha256 %s\n",
 					added.Entry.Model, added.Entry.Version, added.Entry.File,
 					fileSize(added.Entry.Bytes), added.SHA256)
@@ -122,6 +147,8 @@ func newMirrorAddCmd(dir *string) *cobra.Command {
 	c.Flags().StringVar(&model, "model", "", "the model's name, one directory level")
 	c.Flags().StringVar(&version, "version", "", "the version, one directory level; a date works well")
 	c.Flags().StringVar(&as, "as", "", "the filename to save as, for one URL; taken from the URL when omitted")
+	c.Flags().StringVar(&sha, "sha256", "", "the sha256 the file must have, for one URL; looked up for a Hugging Face URL")
+	c.Flags().StringVar(&registry, "registry", hf.DefaultEndpoint, "the registry a resolve URL is looked up in")
 	return c
 }
 
@@ -237,6 +264,10 @@ func newMirrorRemoveCmd(dir *string) *cobra.Command {
 			if err := mirror.Remove(*dir, e); err != nil {
 				return err
 			}
+			// Kept for a mirror kept in step, which otherwise copies it back.
+			if err := mirror.RecordRemoval(*dir, model, version); err != nil {
+				return err
+			}
 			fmt.Fprintf(cmd.OutOrStdout(), "removed %s/%s/%s\n", model, version, file)
 			return nil
 		},
@@ -255,6 +286,7 @@ func newMirrorServeCmd(dir *string) *cobra.Command {
 	var tlsc tlsconf.Config
 	var allow, clients []string
 	var allowPrivate bool
+	var peers []string
 
 	c := &cobra.Command{
 		Use:   "serve",
@@ -317,6 +349,21 @@ func newMirrorServeCmd(dir *string) *cobra.Command {
 				ReadTimeout: time.Minute,
 			})
 
+			// Another mirror kept in step with this one, each copying what
+			// the other has: the cluster's models while one machine is down.
+			if len(peers) > 0 {
+				p := &mirror.Peers{M: mgr, Log: log}
+				for _, addr := range peers {
+					c, err := mirror.NewClient(addr, tlsc, 30*time.Second)
+					if err != nil {
+						return fmt.Errorf("--peer %s: %w", addr, err)
+					}
+					p.Clients = append(p.Clients, c)
+				}
+				go p.Run(cmd.Context())
+				fmt.Fprintf(out, "kept in step with %s, every %s\n", strings.Join(peers, ", "), mirror.PeerInterval)
+			}
+
 			errs := make(chan error, 2)
 			go func() { errs <- fmt.Errorf("serving weights: %w", files.ListenAndServe()) }()
 			fmt.Fprintf(out, "serving %s on %s\n", *dir, listen)
@@ -343,6 +390,9 @@ func newMirrorServeCmd(dir *string) *cobra.Command {
 		},
 	}
 	c.Flags().StringVar(&listen, "listen", ":8081", "address to serve the weights on")
+	c.Flags().StringArrayVar(&peers, "peer", nil,
+		"another mirror's management API to keep in step with, each copying what the other has; repeatable. "+
+			"Give each the other's address in --api-allow (or its certificate in --api-client)")
 	c.Flags().StringVar(&apiListen, "api-listen", ":8082", "address to serve the management API on")
 	c.Flags().StringVar(&base, "base", "http://localhost:8081",
 		"the address nodes use to reach this mirror, as it should appear in catalog sources")

internal/cli/mirror_peer.go

@@ -0,0 +1,224 @@
+package cli
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"regexp"
+	"slices"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/onboard"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/settings"
+)
+
+// A second mirror, so models can still be added and fetched while the first
+// machine is down. Set up from the machine of the first, which it is kept in
+// step with: the first is told of it, it of the first, and the control
+// planes of both.
+
+func newMirrorAddPeerCmd(dir *string) *cobra.Command {
+	var controlPlanes []string
+	var base string
+	cmd := &cobra.Command{
+		Use:   "add-peer [user@]host",
+		Short: "Set up a second mirror on another machine, kept in step with this one",
+		Long: `Run on the machine of the cluster's mirror, as root. It logs in to HOST with
+ssh, installs llmgw there if it is not, and sets up a mirror that keeps in
+step with this one: each copies what the other holds, checksum checked, and
+a model removed from one is removed from the other. This mirror is told of
+it, and the cluster's settings name it (mirror.peers), so while either
+machine is down the control planes use the other and nodes fetch from it.
+On a mirror machine without the control plane's settings file, it prints
+the llmgw ctl config set to run on a control plane instead.
+
+HOST needs room for every model this mirror holds: it copies them all.`,
+		Example: "  sudo llmgw mirror add-peer ubuntu@10.0.0.12 --control-plane 10.0.0.10 --control-plane 10.0.0.12",
+		Args:    cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if os.Geteuid() != 0 {
+				return errors.New("add-peer changes this mirror's service and the cluster's settings: run it as root")
+			}
+			user, host, ok := strings.Cut(args[0], "@")
+			if !ok {
+				user, host = os.Getenv("SUDO_USER"), args[0]
+			}
+			return addMirrorPeer(cmd.Context(), cmd.OutOrStdout(), &onboard.SSH{Addr: host, User: user}, host,
+				*dir, base, controlPlanes, "/etc/llmgw/server.yaml")
+		},
+	}
+	cmd.Flags().StringArrayVar(&controlPlanes, "control-plane", nil,
+		"address of a control plane that manages the mirrors; repeatable (default: this machine)")
+	cmd.Flags().StringVar(&base, "base", "", "the address nodes fetch from on HOST (default: http://HOST:8081)")
+	return cmd
+}
+
+// addMirrorPeer sets up a mirror on a machine reached by remote, kept in
+// step with the one on this machine.
+func addMirrorPeer(ctx context.Context, out io.Writer, remote onboard.Remote, host, dir, base string,
+	controlPlanes []string, configPath string,
+) error {
+	ip, err := ipv4Of(host)
+	if err != nil {
+		return err
+	}
+	here := primaryAddr()
+	if len(controlPlanes) == 0 {
+		controlPlanes = []string{here}
+	}
+	if base == "" {
+		base = "http://" + net.JoinHostPort(ip, "8081")
+	}
+	thisAPI := "http://" + net.JoinHostPort(here, "8082")
+	peerAPI := "http://" + net.JoinHostPort(ip, "8082")
+
+	// llmgw there, the same as here, when it has none.
+	if _, err := remote.Run(ctx, "command -v llmgw >/dev/null", nil); err != nil {
+		exe, err := os.Executable()
+		if err != nil {
+			return err
+		}
+		bin, err := os.ReadFile(exe) //nolint:gosec // this program
+		if err != nil {
+			return err
+		}
+		fmt.Fprintf(out, "  ..    llmgw to %s\n", host)
+		if _, err := remote.Run(ctx, "sudo install -m 755 /dev/stdin /usr/local/bin/llmgw", bin); err != nil {
+			return fmt.Errorf("installing llmgw on %s: %w", host, err)
+		}
+	}
+
+	// The mirror there: its management API for the control planes and this
+	// mirror, which reads it; kept in step with this one.
+	allow := append([]string{}, controlPlanes...)
+	if !slices.Contains(allow, here) {
+		allow = append(allow, here)
+	}
+	script := "sudo llmgw mirror init --dir " + shellQuote(dir) + " --base " + shellQuote(base) + " --peer " + shellQuote(thisAPI)
+	for _, a := range allow {
+		script += " --control-plane " + shellQuote(a)
+	}
+	fmt.Fprintf(out, "  ..    the mirror on %s\n", host)
+	if b, err := remote.Run(ctx, script, nil); err != nil {
+		return fmt.Errorf("the mirror on %s: %w\n%s", host, err, b)
+	}
+
+	// This mirror told of it, and to let it read this one's API.
+	changed, err := addToMirrorUnit(mirrorUnitPath, peerAPI, ip)
+	if err != nil {
+		return err
+	}
+	if changed {
+		in := &serverInit{out: out}
+		if err := in.systemctl(ctx, "daemon-reload"); err != nil {
+			return err
+		}
+		if err := in.systemctl(ctx, "restart", "llmgw-mirror"); err != nil {
+			return err
+		}
+	}
+	fmt.Fprintf(out, "  ok    this mirror keeps in step with %s\n", peerAPI)
+
+	// The control planes told of both.
+	return nameMirrorPeer(out, configPath, peerAPI)
+}
+
+// nameMirrorPeer names a peer in the cluster's settings. A mirror on a
+// machine of its own has neither the settings file nor the store: it says
+// what to run on a control plane.
+func nameMirrorPeer(out io.Writer, configPath, peerAPI string) error {
+	if _, err := os.Stat(configPath); errors.Is(err, os.ErrNotExist) {
+		fmt.Fprintf(out, "  !!    this machine has no %s, so the cluster's settings are not changed here. On a control plane:\n"+
+			"          sudo llmgw ctl config set mirror.peers '[%s]'\n"+
+			"        (with any peers already named, which llmgw ctl config get mirror.peers shows)\n", configPath, peerAPI)
+		return nil
+	}
+	if err := addMirrorPeerSetting(configPath, peerAPI); err != nil {
+		return err
+	}
+	fmt.Fprintf(out, "  ok    mirror.peers names %s; the control planes use it while this one is down\n", peerAPI)
+	return nil
+}
+
+// addToMirrorUnit adds a peer and the address allowed to read this mirror's
+// API to its systemd unit, and says whether it changed.
+func addToMirrorUnit(path, peer, allow string) (bool, error) {
+	b, err := os.ReadFile(path) //nolint:gosec // the mirror's unit
+	if err != nil {
+		return false, fmt.Errorf("this machine has no mirror to keep in step (%s): run add-peer on the mirror's machine", path)
+	}
+	unit := string(b)
+	re := regexp.MustCompile(`(?m)^ExecStart=.*$`)
+	line := re.FindString(unit)
+	if line == "" {
+		return false, fmt.Errorf("%s has no ExecStart", path)
+	}
+	next := line
+	if !strings.Contains(next, "--peer "+peer) {
+		next += " --peer " + peer
+	}
+	if !strings.Contains(next, "--api-allow "+allow+" ") && !strings.HasSuffix(next, "--api-allow "+allow) &&
+		strings.Contains(next, "--api-listen :") {
+		next += " --api-allow " + allow
+	}
+	if next == line {
+		return false, nil
+	}
+	return true, os.WriteFile(path, []byte(strings.Replace(unit, line, next, 1)), 0o644)
+}
+
+// addMirrorPeerSetting names a peer in mirror.peers: in the cluster's
+// settings when the store holds them, else in server.yaml.
+func addMirrorPeerSetting(path, peer string) error {
+	add := func(doc *settings.Doc) error {
+		var peers []string
+		if n := doc.Node([]string{"mirror", "peers"}); n != nil {
+			_ = n.Decode(&peers)
+		}
+		if slices.Contains(peers, peer) {
+			return nil
+		}
+		list := "[" + strings.Join(append(peers, peer), ", ") + "]"
+		return doc.SetYAML([]string{"mirror", "peers"}, list)
+	}
+	changed, err := changeStoredSettings(path, "a second mirror (llmgw mirror add-peer)", add)
+	if err != nil || changed {
+		return err
+	}
+	doc, err := settings.Open(path)
+	if err != nil {
+		return err
+	}
+	if err := add(doc); err != nil {
+		return err
+	}
+	_, err = doc.Save(nil)
+	return err
+}
+
+// ensureSecondMirror sets up the mirror kept in step with this machine's on
+// the store machine chosen, reached as the store's setup reached it.
+func (in *serverInit) ensureSecondMirror(ctx context.Context) error {
+	if !in.standbys {
+		return errors.New("it needs --standbys: without them this mirror's API answers this machine alone, which the second cannot read")
+	}
+	i := in.secondMirror - 1
+	if i < 0 || i >= len(in.patroniNodes) {
+		return fmt.Errorf("there is no database machine %d to put it on", in.secondMirror)
+	}
+	if in.noMirror || in.mirrorURL != "" {
+		return errors.New("it keeps in step with a mirror on this machine, and there is none")
+	}
+	n := in.patroniNodes[i]
+	fmt.Fprintf(in.out, "  ..    a second mirror on %s\n", n.Name)
+	if err := addMirrorPeer(ctx, in.out, n.Remote, n.IP, in.mirrorRoot(), "", in.mirrorAllow(), in.configPath()); err != nil {
+		return err
+	}
+	in.done("a second mirror on %s (%s), kept in step with this one", n.Name, n.IP)
+	return nil
+}

internal/cli/mirror_peer_test.go

@@ -0,0 +1,85 @@
+package cli
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestAPeerIsAddedToTheMirrorsUnitOnce(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "llmgw-mirror.service")
+	unit := mirrorUnitFor("/srv/models", ":8082", "http://10.0.0.10:8081", []string{"10.0.0.10"}, nil, "test")
+	if err := os.WriteFile(path, []byte(unit), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	changed, err := addToMirrorUnit(path, "http://10.0.0.12:8082", "10.0.0.12")
+	if err != nil || !changed {
+		t.Fatalf("changed %v %v", changed, err)
+	}
+	b, _ := os.ReadFile(path)
+	if !strings.Contains(string(b), "--peer http://10.0.0.12:8082") || !strings.Contains(string(b), "--api-allow 10.0.0.12") {
+		t.Errorf("unit:\n%s", b)
+	}
+	if changed, _ := addToMirrorUnit(path, "http://10.0.0.12:8082", "10.0.0.12"); changed {
+		t.Error("added twice")
+	}
+	// A mirror whose API is on loopback alone is not opened by the back door.
+	lo := mirrorUnitFor("/srv/models", "127.0.0.1:8082", "http://10.0.0.10:8081", nil, nil, "test")
+	_ = os.WriteFile(path, []byte(lo), 0o644)
+	_, _ = addToMirrorUnit(path, "http://10.0.0.12:8082", "10.0.0.12")
+	if b, _ := os.ReadFile(path); strings.Contains(string(b), "--api-allow") {
+		t.Errorf("a loopback mirror was opened:\n%s", b)
+	}
+}
+
+func TestASecondMirrorIsNamedInTheSettings(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "server.yaml")
+	if err := os.WriteFile(path, []byte("listen: \":8080\"\nmirror:\n  api: http://10.0.0.10:8082\n"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	for range 2 {
+		if err := addMirrorPeerSetting(path, "http://10.0.0.12:8082"); err != nil {
+			t.Fatal(err)
+		}
+	}
+	b, _ := os.ReadFile(path)
+	if strings.Count(string(b), "10.0.0.12:8082") != 1 || !strings.Contains(string(b), "peers") {
+		t.Errorf("server.yaml:\n%s", b)
+	}
+}
+
+func TestTheSetupOffersASecondMirrorOnAStoreMachine(t *testing.T) {
+	in := newDefaultServerInit()
+	f := newInstallForm(&in, "ctl", []string{"10.0.0.5"}, true)
+	f.secondMirror.Choice = 1
+	if !f.secondMirror.Show() {
+		t.Fatal("not offered with the mirror on this machine")
+	}
+	f.mirrorWhere.Choice = 1
+	if f.secondMirror.Show() {
+		t.Error("offered with the mirror elsewhere")
+	}
+	f.mirrorWhere.Choice = 0
+	in.secondMirror = 1
+	in.patroni = []string{"ubuntu@10.0.0.11", "ubuntu@10.0.0.12"}
+	if got := strings.Join(in.initFlags(), " "); !strings.Contains(got, "--second-mirror 1") {
+		t.Errorf("flags %s", got)
+	}
+	// Without standbys this mirror answers itself alone: the second could not read it.
+	in.standbys = false
+	if err := in.ensureSecondMirror(t.Context()); err == nil || !strings.Contains(err.Error(), "standbys") {
+		t.Errorf("without standbys: %v", err)
+	}
+}
+
+func TestAMirrorOnAMachineOfItsOwnSaysWhatToRunOnAControlPlane(t *testing.T) {
+	var out bytes.Buffer
+	if err := nameMirrorPeer(&out, filepath.Join(t.TempDir(), "server.yaml"), "http://10.0.0.12:8082"); err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(out.String(), "llmgw ctl config set mirror.peers '[http://10.0.0.12:8082]'") {
+		t.Errorf("%s", out.String())
+	}
+}

internal/cli/mirrorinit.go

@@ -29,6 +29,7 @@ import (
 func newMirrorInitCmd(dir *string) *cobra.Command {
 	var (
 		controlPlanes []string
+		peers         []string
 		base          string
 		noFirewall    bool
 	)
@@ -61,7 +62,7 @@ Safe to run again: it changes only what differs.`,
 			if _, err := parseAllow(controlPlanes); err != nil {
 				return err
 			}
-			if err := mirrorInit(cmd.Context(), cmd.OutOrStdout(), *dir, base, controlPlanes); err != nil {
+			if err := mirrorInit(cmd.Context(), cmd.OutOrStdout(), *dir, base, controlPlanes, peers); err != nil {
 				return err
 			}
 			if !noFirewall {
@@ -80,6 +81,9 @@ Safe to run again: it changes only what differs.`,
 	}
 	cmd.Flags().StringArrayVar(&controlPlanes, "control-plane", nil,
 		"address of the control plane that manages this mirror; repeatable")
+	cmd.Flags().StringArrayVar(&peers, "peer", nil,
+		"another mirror's management API to keep in step with, http://host:8082; repeatable. "+
+			"Its machine must be among --control-plane, to read this one")
 	cmd.Flags().BoolVar(&noFirewall, "no-firewall", false,
 		"leave the firewall alone, instead of keeping the mirror's ports to the cluster's networks")
 	cmd.Flags().StringVar(&base, "base", "",
@@ -87,7 +91,7 @@ Safe to run again: it changes only what differs.`,
 	return cmd
 }
 
-func mirrorInit(ctx context.Context, out io.Writer, dir, base string, controlPlanes []string) error {
+func mirrorInit(ctx context.Context, out io.Writer, dir, base string, controlPlanes, peers []string) error {
 	in := &serverInit{user: "llmgw", stateDir: "/var/lib/llmgw", out: out}
 	if err := in.ensureUser(ctx); err != nil {
 		return err
@@ -105,7 +109,7 @@ func mirrorInit(ctx context.Context, out io.Writer, dir, base string, controlPla
 		}
 		base = "http://" + net.JoinHostPort(addr, "8081")
 	}
-	unit := mirrorUnitFor(dir, ":8082", base, controlPlanes,
+	unit := mirrorUnitFor(dir, ":8082", base, controlPlanes, peers,
 		"'llmgw mirror init'. Bytes on :8081 for every node; the\n# management API on :8082, for the control plane only.")
 	changed, err := in.writeUnit(mirrorUnitPath, unit)
 	if err != nil {

internal/cli/model.go

@@ -18,6 +18,7 @@ import (
 
 	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/control/catalog"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/control/modelserve"
 	"gitea.mynodes.xyz/ilker/llmgw/internal/sourcecheck"
 )
 
@@ -33,7 +34,7 @@ func newModelCmd(client func() *ctlClient, asJSON *bool) *cobra.Command {
 		Use:   "model",
 		Short: "Add or remove models while the cluster is running",
 	}
-	c.AddCommand(newModelAddCmd(client), newModelPresetsCmd(client, asJSON), newModelRemoveCmd(client), newModelPlanCmd(client),
+	c.AddCommand(newModelStopCmd(client), newModelStartCmd(client), newModelContextCmd(client), newModelGPUsCmd(client), newModelAddCmd(client), newModelPresetsCmd(client, asJSON), newModelRemoveCmd(client), newModelPlanCmd(client),
 		newResourcesCmd(client), newClassCmd(client), newOwnerCmd(client),
 		newTargetCmd(client, asJSON), newAdaptersCmd(client),
 		newModelServeCmd(client), newModelUpdatesCmd(client, asJSON), newModelUpdateCmd(client),
@@ -162,21 +163,104 @@ func readModelFile(path string) (catalog.Model, error) {
 }
 
 func newModelRemoveCmd(client func() *ctlClient) *cobra.Command {
-	return &cobra.Command{
+	var purge bool
+	c := &cobra.Command{
 		Use:   "remove <name>",
-		Short: "Remove a model that was added at runtime",
+		Short: "Remove a model that was added at runtime, and with --purge its files",
 		Long: "Only models added at runtime. One declared in server.yaml would come\n" +
 			"back on the next restart, so removing it here would leave the cluster\n" +
 			"disagreeing with its own configuration until then.\n\n" +
 			"Its replicas are stopped on the next pass, after the endpoint has been\n" +
-			"withdrawn, so traffic stops before the engine does.",
+			"withdrawn, so traffic stops before the engine does.\n\n" +
+			"Its files stay on the mirror and the nodes, for adding it again. With\n" +
+			"--purge they go too: every version of it on the mirror (a mirror kept in\n" +
+			"step follows), and the nodes' copies once its replicas have stopped.\n" +
+			"What another model uses stays. To take a model out of service and keep\n" +
+			"it, use llmgw ctl model stop.",
+		Example: "  llmgw ctl model remove qwen-7b\n" +
+			"  llmgw ctl model remove qwen-7b --purge   # its files on the mirror and the nodes too",
 		Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			var res map[string]string
-			if err := client().delete(cmd.Context(), "/api/v1/models/"+args[0], &res); err != nil {
+			out := cmd.OutOrStdout()
+			if !purge {
+				var res map[string]string
+				if err := client().delete(cmd.Context(), "/api/v1/models/"+args[0], &res); err != nil {
+					return err
+				}
+				fmt.Fprintf(out, "%s removed. Its files stay on the mirror and the nodes; --purge deletes them.\n", args[0])
+				return nil
+			}
+			var v adminapi.PurgeView
+			if err := client().patient(3*time.Minute).delete(cmd.Context(), "/api/v1/models/"+args[0]+"?purge=true", &v); err != nil {
 				return err
 			}
-			fmt.Fprintf(cmd.OutOrStdout(), "%s removed.\n", args[0])
+			fmt.Fprintf(out, "%s removed.\n", v.Removed)
+			for _, m := range v.Mirror {
+				fmt.Fprintf(out, "  mirror  %s deleted\n", m)
+			}
+			for _, m := range v.Kept {
+				fmt.Fprintf(out, "  mirror  %s kept: another model uses it\n", m)
+			}
+			var freed int64
+			for _, n := range v.Nodes {
+				if n.Error != "" {
+					fmt.Fprintf(out, "  node    %s: %s\n", n.Node, n.Error)
+					continue
+				}
+				freed += n.Bytes
+				fmt.Fprintf(out, "  node    %s: %d file(s), %s\n", n.Node, n.Files, humanBytes(n.Bytes))
+			}
+			if len(v.Mirror) == 0 && len(v.Nodes) == 0 && v.Note == "" {
+				fmt.Fprintln(out, "  it had no files of its own on the mirror or the nodes")
+			}
+			if freed > 0 {
+				fmt.Fprintf(out, "  %s freed on the nodes\n", humanBytes(freed))
+			}
+			if v.Note != "" {
+				fmt.Fprintln(out, "  "+v.Note)
+			}
+			return nil
+		},
+	}
+	c.Flags().BoolVar(&purge, "purge", false, "delete its files from the mirror and the nodes as well")
+	return c
+}
+
+func newModelStopCmd(client func() *ctlClient) *cobra.Command {
+	return &cobra.Command{
+		Use:   "stop <model>",
+		Short: "Take a model out of service and keep it: none of its replicas run until it is started",
+		Long: "Its replicas stop; it stays in the catalog with its files, and a request\n" +
+			"for it is told an administrator stopped it. What it was scaled to is kept:\n" +
+			"llmgw ctl model start runs it again as it was.",
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			var v adminapi.ScaleResponse
+			if err := client().post(cmd.Context(), "/api/v1/models/"+args[0]+"/stop", nil, &v); err != nil {
+				return err
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "%s stopped: its replicas stop on the next pass. It is kept; "+
+				"llmgw ctl model start %s runs it again.\n", v.Model, v.Model)
+			return nil
+		},
+	}
+}
+
+func newModelStartCmd(client func() *ctlClient) *cobra.Command {
+	return &cobra.Command{
+		Use:   "start <model>",
+		Short: "Run a stopped model again, scaled as it was when it was stopped",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			var v adminapi.ScaleResponse
+			if err := client().post(cmd.Context(), "/api/v1/models/"+args[0]+"/start", nil, &v); err != nil {
+				return err
+			}
+			how := fmt.Sprintf("%d replica(s)", v.Min)
+			if v.OnDemand {
+				how = "on demand"
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "%s started: %s, max %d. Watch it with llmgw ctl models.\n", v.Model, how, v.Max)
 			return nil
 		},
 	}
@@ -386,3 +470,112 @@ func newAdaptersCmd(client func() *ctlClient) *cobra.Command {
 	c.Flags().StringArrayVar(&remove, "remove", nil, "an adapter's name; repeatable")
 	return c
 }
+
+func newModelContextCmd(client func() *ctlClient) *cobra.Command {
+	var slots int
+	c := &cobra.Command{
+		Use:   "context <model> <tokens>",
+		Short: "Change how much one request to a served model may use",
+		Long: "The context lives in three places: the catalog (what a request may use, and\n" +
+			"what it may answer), the engine's arguments (llama.cpp's --ctx-size and\n" +
+			"--parallel, vLLM's --max-model-len), and the memory the KV cache takes. This\n" +
+			"changes all three together. It refuses more than the model was trained for,\n" +
+			"and a context its cards would not hold, saying what each would need. Its\n" +
+			"replicas are then started again on it, each new one before the old stops.\n\n" +
+			"--slots is how many requests a llama.cpp replica answers at once; its pool is\n" +
+			"slots × tokens. Left out, it keeps what it has.",
+		Example: "  llmgw ctl model context qwen3-coder-30b 65536\n" +
+			"  llmgw ctl model context qwen2.5-7b 16384 --slots 4",
+		Args: cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			tokens, err := strconv.Atoi(args[1])
+			if err != nil {
+				return fmt.Errorf("the context is a whole number of tokens, not %q", args[1])
+			}
+			body, _ := json.Marshal(modelserve.ContextRequest{Tokens: tokens, Slots: slots})
+			var v modelserve.ContextChange
+			if err := client().patient(time.Minute).post(cmd.Context(), "/api/v1/models/"+args[0]+"/context", body, &v); err != nil {
+				return err
+			}
+			out := cmd.OutOrStdout()
+			fmt.Fprintf(out, "%s: %d → %d tokens a request, answers up to %d", v.Model, v.Before, v.After, v.MaxOutput)
+			if v.Trained > 0 {
+				fmt.Fprintf(out, " (trained for %d)", v.Trained)
+			}
+			fmt.Fprintln(out)
+			for _, p := range v.Profiles {
+				line := "  " + p.Profile + " (" + p.Engine + "): " + strings.Join(p.Args, " ")
+				switch {
+				case p.Before != "" && p.After != "":
+					line += "; " + p.Before + " → " + p.After
+				case p.After != "":
+					line += "; " + p.After
+				}
+				fmt.Fprintln(out, line)
+			}
+			if v.Note != "" {
+				fmt.Fprintln(out, "  note: "+v.Note)
+			}
+			if v.Restarted > 0 {
+				fmt.Fprintf(out, "%d replica(s) started again on it, each new one before the old stops: llmgw ctl replicas --model %s\n", v.Restarted, v.Model)
+			}
+			return nil
+		},
+	}
+	c.Flags().IntVar(&slots, "slots", 0, "llama.cpp: requests a replica answers at once (default: as it is)")
+	return c
+}
+
+func newModelGPUsCmd(client func() *ctlClient) *cobra.Command {
+	var profile string
+	var inPlace bool
+	c := &cobra.Command{
+		Use:   "gpus <model> <cards>",
+		Short: "Spread a served model over more cards, or fewer",
+		Long: "How many cards of one node each replica uses. vLLM, SGLang and TensorRT-LLM\n" +
+			"spread the model by tensor parallel, which needs the count to divide the\n" +
+			"model's KV heads or be divided by them; llama.cpp splits its layers over the\n" +
+			"cards. It refuses a count a node does not have, and one whose cards would not\n" +
+			"hold the model and its context, saying what each would need. Its replicas are\n" +
+			"then started again on it, each new one beside the old before it stops.\n\n" +
+			"With no node free enough beside the running replicas — a node of two cards,\n" +
+			"the model on one — --in-place stops each replica first: the model does not\n" +
+			"answer while the new one loads.\n\n" +
+			"--profile names the profile for a model with more than one on cards.",
+		Example: "  llmgw ctl model gpus qwen3-coder-30b 2\n" +
+			"  llmgw ctl model gpus llama-70b 4 --profile h100 --in-place",
+		Args: cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			n, err := strconv.Atoi(args[1])
+			if err != nil {
+				return fmt.Errorf("the cards are a whole number, not %q", args[1])
+			}
+			body, _ := json.Marshal(modelserve.GPUsRequest{GPUs: n, Profile: profile, InPlace: inPlace})
+			var v modelserve.GPUsChange
+			if err := client().patient(time.Minute).post(cmd.Context(), "/api/v1/models/"+args[0]+"/gpus", body, &v); err != nil {
+				return err
+			}
+			out := cmd.OutOrStdout()
+			fmt.Fprintf(out, "%s: %d → %d %s card(s) a replica (%s, %s)\n", v.Model, v.Before, v.After, v.Class, v.Profile, v.Engine)
+			if v.PerCard != "" {
+				fmt.Fprintln(out, "  "+v.PerCard)
+			}
+			if len(v.Args) > 0 {
+				fmt.Fprintln(out, "  args: "+strings.Join(v.Args, " "))
+			}
+			if v.Note != "" {
+				fmt.Fprintln(out, "  note: "+v.Note)
+			}
+			switch {
+			case v.Restarted > 0 && v.InPlace:
+				fmt.Fprintf(out, "%d replica(s) stopped and started again on it, one by one: llmgw ctl replicas --model %s\n", v.Restarted, v.Model)
+			case v.Restarted > 0:
+				fmt.Fprintf(out, "%d replica(s) started again on it, each new one before the old stops: llmgw ctl replicas --model %s\n", v.Restarted, v.Model)
+			}
+			return nil
+		},
+	}
+	c.Flags().StringVar(&profile, "profile", "", "the profile to change, for a model with several on cards")
+	c.Flags().BoolVar(&inPlace, "in-place", false, "stop each replica before its replacement starts, when there is no room beside it")
+	return c
+}

internal/cli/model_serve.go

@@ -64,11 +64,15 @@ func newModelServeCmd(client func() *ctlClient) *cobra.Command {
 		"--embedding, 32 slots of 1024 tokens unless --ctx-pool or --context-length says otherwise")
 	f.StringVar(&req.Format, "format", "gguf", "gguf, run by llama.cpp, or safetensors: the original weights, run by vLLM on GPUs")
 	f.BoolVar(&req.CPU, "cpu", false, "run it on the CPU, whatever the plan says")
+	f.StringVar(&req.Engine, "engine", "", "strata, for a family Strata runs: one card and the experts in RAM; "+
+		"llamacpp to keep it off Strata (default: the plan's best)")
 	f.StringVar(&req.GPUClass, "gpu-class", "", "run it on GPUs of this class, whatever the plan says")
 	f.IntVar(&req.GPUsPerNode, "gpus", 0, "with --gpu-class: the cards one replica takes on each node (default 1)")
 	f.IntVar(&req.Nodes, "nodes", 0, "with --gpu-class: the nodes one replica spans, over a fabric (vLLM only)")
 	f.IntVar(&req.TP, "tp", 0, "the older name of --gpus")
 	_ = f.MarkHidden("tp")
+	f.StringToStringVar(&req.Env, "env", nil,
+		"KEY=VALUE in the engine's environment on every node, e.g. NCCL_DEBUG=INFO; repeatable")
 	f.BoolVar(&req.Fallbacks, "fallbacks", false, "also add the next best ways to run it, used when the first is busy")
 	f.BoolVar(&detach, "detach", false, "start it and return: it runs on the control plane; `llmgw ctl jobs` follows it")
 	f.StringVar(&req.Name, "name", "", "the catalog name (default: from the repository)")

internal/cli/modelplan.go

@@ -291,14 +291,14 @@ func planFiles(cmd *cobra.Command, client func() *ctlClient, repo, format string
 	}
 	fmt.Fprintln(out)
 	w := tabTo(out)
-	fmt.Fprintln(w, "FILE\tSIZE\tBEST WAY\tHOLDS\tOF\tNOW")
+	fmt.Fprintln(w, "FILE\tSIZE\tBEST WAY\tA CARD\tOF\tALL CARDS\tNOW")
 	for _, a := range p.Artifacts {
 		name := a.Name
 		if a.Shards > 1 && a.Format == "gguf" {
 			name += fmt.Sprintf(" (%d parts)", a.Shards)
 		}
 		if a.Best == nil {
-			fmt.Fprintf(w, "%s\t%s\tfits nowhere\t\t\t\n", name, bytesShort(a.Bytes))
+			fmt.Fprintf(w, "%s\t%s\tfits nowhere\t\t\t\t\n", name, bytesShort(a.Bytes))
 			continue
 		}
 		b := a.Best
@@ -306,11 +306,14 @@ func planFiles(cmd *cobra.Command, client func() *ctlClient, repo, format string
 		if b.FreeNow {
 			now = "free"
 		}
-		holds := fmt.Sprintf("%.1f GB a card", b.NeedGB)
+		holds, all := fmt.Sprintf("%.1f GB", b.NeedGB), fmt.Sprintf("%.0f GB", b.TotalGB())
 		if b.CPU {
-			holds = fmt.Sprintf("%.1f GB of RAM", b.NeedGB)
+			holds, all = fmt.Sprintf("%.1f GB of RAM", b.NeedGB), "-"
 		}
-		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%.0f GB\t%s\n", name, bytesShort(a.Bytes), b.Label(), holds, b.HaveGB, now)
+		if b.Engine == "strata" {
+			holds, all = fmt.Sprintf("%.0f GB of RAM", b.NeedGB), "1 card"
+		}
+		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%.0f GB\t%s\t%s\n", name, bytesShort(a.Bytes), b.Label(), holds, b.HaveGB, all, now)
 	}
 	_ = w.Flush()
 	rec, ok := p.Recommended()
@@ -318,7 +321,11 @@ func planFiles(cmd *cobra.Command, client func() *ctlClient, repo, format string
 		fmt.Fprintln(out, "\nNo file fits this cluster as it is: a smaller context (--context), or more memory.")
 		return errDoesNotFit
 	}
-	fmt.Fprintf(out, "\nBest: %s on %s.\n", rec.Artifact, rec.Label())
+	fmt.Fprintf(out, "\nBest: %s on %s: %s.\n", rec.Artifact, rec.Label(), rec.MemoryText())
+	if p.KVBytesPerToken > 0 {
+		fmt.Fprintf(out, "The context costs %.2f GB per 1000 tokens, the whole model (--context to plan another).\n",
+			modelplan.GB(p.KVBytesPerToken*1000))
+	}
 	if len(p.Options) > 1 {
 		fmt.Fprintln(out, "\nEvery way, best first:")
 		w = tabTo(out)
@@ -327,7 +334,7 @@ func planFiles(cmd *cobra.Command, client func() *ctlClient, repo, format string
 			if o.FreeNow {
 				now = "free"
 			}
-			fmt.Fprintf(w, "  %s\t%s\t%.1f of %.0f GB\t%d host(s)\t%s\n", o.Artifact, o.Label(), o.NeedGB, o.HaveGB, o.Hosts, now)
+			fmt.Fprintf(w, "  %s\t%s\t%s\t%d host(s)\t%s\n", o.Artifact, o.Label(), o.MemoryText(), o.Hosts, now)
 		}
 		_ = w.Flush()
 	}
@@ -335,6 +342,10 @@ func planFiles(cmd *cobra.Command, client func() *ctlClient, repo, format string
 	if p.Format == "safetensors" {
 		fmt.Fprint(out, " --format safetensors")
 	}
+	if rec.Engine == "strata" {
+		fmt.Fprintf(out, " --file %s --engine strata\n", rec.Artifact)
+		return nil
+	}
 	fmt.Fprintln(out, " --fallbacks")
 	return nil
 }

internal/cli/node.go

@@ -186,7 +186,7 @@ func (na *nodeAdd) prepare() error {
 	}
 	// Where the mirror serves model files, for the node to be asked to reach.
 	if cfg, err := loadEffectiveConfig(na.serverCfg); err == nil && cfg.Mirror.API != "" {
-		if mc, err := mirror.NewClient(cfg.Mirror.API, cfg.Mirror.TLS, 5*time.Second); err == nil {
+		if mc, err := mirror.NewFailoverClient(append([]string{cfg.Mirror.API}, cfg.Mirror.Peers...), cfg.Mirror.TLS, 5*time.Second); err == nil {
 			ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 			if list, err := mc.List(ctx); err == nil {
 				o.MirrorBase = list.Base

internal/cli/org_test.go

@@ -131,3 +131,33 @@ func TestKeyBudgetsAreWholeUnits(t *testing.T) {
 		}
 	}
 }
+
+// A limit given alone changes that limit alone: granting a tool keeps the
+// scope's rate. --replace writes the row whole, as the console's form does.
+func TestALimitGivenAloneLeavesTheOthersAtTheScope(t *testing.T) {
+	db := filepath.Join(t.TempDir(), "s.db")
+	mustRun(t, db, "org", "add", "org", "Acme")
+	mustRun(t, db, "org", "add", "team", "platform")
+	mustRun(t, db, "org", "add", "project", "gateway")
+	mustRun(t, db, "keys", "limits", "--scope", "project", "--id", "gateway", "--rpm", "30")
+	mustRun(t, db, "keys", "limits", "--scope", "project", "--id", "gateway", "--tools", "jira.*")
+	read := func() store.Limits {
+		s, err := store.Open(context.Background(), db)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer s.Close()
+		all, _ := s.AllLimits(context.Background())
+		for _, l := range all {
+			return l
+		}
+		return store.Limits{}
+	}
+	if l := read(); l.RPM == nil || *l.RPM != 30 || len(l.AllowedTools) != 1 {
+		t.Errorf("after a tool grant: rpm %v, tools %v", l.RPM, l.AllowedTools)
+	}
+	mustRun(t, db, "keys", "limits", "--replace", "--scope", "project", "--id", "gateway", "--tpm", "1000")
+	if l := read(); l.RPM != nil || l.AllowedTools != nil || l.TPM == nil {
+		t.Errorf("after --replace: %+v", l)
+	}
+}

internal/cli/root.go

@@ -55,6 +55,7 @@ func Root() *cobra.Command {
 		newBundleCmd(),
 		newSimEngineCmd(),
 		newComfyUIGateCmd(),
+		newStrataServeCmd(),
 		newDoctorCmd(),
 		newNodeCmd(),
 		newSelfUpgradeCmd(),

internal/cli/server.go

@@ -76,6 +76,7 @@ func newServerCmd() *cobra.Command {
 
 	cmd := &cobra.Command{
 		Use:   "server",
+		Args:  cobra.NoArgs,
 		Short: "Run the router (phase 1; the control plane arrives in phase 3)",
 		Long: "Serves the OpenAI API in front of a set of engine replicas.\n\n" +
 			"In this phase the replica list is static: give it in the config file, or\n" +
@@ -138,6 +139,26 @@ func newServerCmd() *cobra.Command {
 				_ = shutdownTracing(sctx)
 			}()
 
+			// The ports before anything else: a second server on this machine,
+			// whose ports are taken, must stop here, not go on to compete for
+			// the lease and lead a cluster no request can reach.
+			apiLn, err := net.Listen("tcp", cfg.Listen)
+			if err != nil {
+				return fmt.Errorf("listening on %s: %w", cfg.Listen, err)
+			}
+			if cfg.MaxConnections > 0 {
+				// Past this, new connections wait in the kernel's backlog
+				// rather than each taking a goroutine and its buffers.
+				apiLn = netutil.LimitListener(apiLn, cfg.MaxConnections)
+			}
+			adminLn, err := net.Listen("tcp", cfg.AdminListen)
+			if err != nil {
+				_ = apiLn.Close()
+				return fmt.Errorf("listening on %s: %w", cfg.AdminListen, err)
+			}
+			defer apiLn.Close()
+			defer adminLn.Close()
+
 			rt, err := router.New(cfg, log)
 			if err != nil {
 				return err
@@ -418,6 +439,9 @@ func newServerCmd() *cobra.Command {
 					}
 					// The cluster's settings, each change checked against this
 					// machine's own keys before it is kept.
+					api.SetMCP(st)
+					rt.SetAdminMCP(http.HandlerFunc(api.MCP))
+					api.SetAuth(&adminapi.AuthAdmin{Status: rt.AuthStatus, TestLDAP: rt.TestDirectory, Secrets: st, Log: log})
 					api.SetSettings(&adminapi.Settings{Store: st, LocalKeys: config.LocalKeys(),
 						Check: func(body []byte) error { return checkClusterSettings(configPath, body) }})
 					// And the same document on the portal, for administrators.
@@ -429,6 +453,9 @@ func newServerCmd() *cobra.Command {
 				if st := rt.Store(); st != nil {
 					svc := modelsvc.New(cfg.Models, st, admin, log)
 					svc.SetCheck(servableCheck(cfg.WantedEngines()["llamacpp"]))
+					// What is added from the registry is pinned to the
+					// commit it is at, with each file's sha256 for the nodes.
+					svc.SetRegistry(hf.New(cfg.Mirror.Registry, 30*time.Second))
 					// Other llmgw clusters' models, offered as PEER/MODEL:
 					// read before the catalog is built, so a model that falls
 					// back to one is whole at startup.
@@ -543,18 +570,33 @@ func newServerCmd() *cobra.Command {
 			// rather than turning into a broken admin page hours later when
 			// somebody finally opens it.
 			if cfg.Mirror.API != "" {
-				mc, err := mirror.NewClient(cfg.Mirror.API, cfg.Mirror.TLS, cfg.Mirror.Timeout)
+				mirrors := append([]string{cfg.Mirror.API}, cfg.Mirror.Peers...)
+				mc, err := mirror.NewFailoverClient(mirrors, cfg.Mirror.TLS, cfg.Mirror.Timeout)
 				if err != nil {
 					return fmt.Errorf("the model mirror: %w", err)
 				}
+				// Mirrors kept in step: a node is given a model's file on one
+				// that answers while the one the catalog names is down.
+				if len(cfg.Mirror.Peers) > 0 {
+					src, err := mirror.NewSources(mirrors, cfg.Mirror.TLS, log)
+					if err != nil {
+						return fmt.Errorf("the model mirrors: %w", err)
+					}
+					go src.Run(ctx)
+					agentsvc.SetSourceRewrite(src.Rewrite)
+				}
 				rt.SetMirror(mc)
+				if adminAPI != nil {
+					// A model removed with its files is removed from it too.
+					adminAPI.SetPurgeMirror(mc)
+				}
 				if fwPub != nil {
 					fwPub.setMirror(mc)
 				}
 				// Adapters trained on the nodes are kept there too; sending one
 				// takes longer than the mirror's usual answers.
 				if adminAPI != nil {
-					if up, err := mirror.NewClient(cfg.Mirror.API, cfg.Mirror.TLS, 10*time.Minute); err == nil {
+					if up, err := mirror.NewFailoverClient(mirrors, cfg.Mirror.TLS, 10*time.Minute); err == nil {
 						adminAPI.SetTrainMirror(up)
 					}
 				}
@@ -572,7 +614,7 @@ func newServerCmd() *cobra.Command {
 						// Updates: the catalog in force, the service that
 						// changes it, and what replaces replicas.
 						Current: func() []catalog.Model { return admin.Catalog().Models() },
-						Models:  catalogSvc, Restart: admin.Reconciler().Restart,
+						Models:  catalogSvc, Restart: admin.Reconciler().Restart, RestartInPlace: admin.Reconciler().RestartInPlace,
 						Pool: adminAPI.PoolNodes, Notify: notifier,
 						// Canaries: how the router saw each side serve.
 						CanaryStats: rt.CanaryStats, ResetCanary: rt.ResetCanary,
@@ -585,6 +627,7 @@ func newServerCmd() *cobra.Command {
 						// A judge a policy names and the catalog lacks is
 						// fetched and served, on the leader.
 						keeper := &judgeKeeper{
+							grace:   judgeGrace,
 							library: gate.Library,
 							models:  func() []catalog.Model { return admin.Catalog().Models() },
 							serve:   serve,
@@ -593,6 +636,25 @@ func newServerCmd() *cobra.Command {
 							},
 							gpus: func() []adminapi.ClassUse { return adminAPI.Summary().GPUs },
 							log:  log,
+							// An earlier install's judge, moved to today's figures.
+							profiles: catalogSvc,
+							restart:  admin.Reconciler().Restart,
+							replicas: func(model string) []string {
+								var ids []string
+								for _, r := range admin.Reconciler().ReadyReplicas() {
+									if r.Model == model {
+										ids = append(ids, r.ID)
+									}
+								}
+								return ids
+							},
+							nodeCPUs: func() []int {
+								var out []int
+								for _, n := range admin.Nodes() {
+									out = append(out, n.CPUCount)
+								}
+								return out
+							},
 						}
 						go keeper.run(ctx, 30*time.Second)
 					}
@@ -642,21 +704,6 @@ func newServerCmd() *cobra.Command {
 				ReadTimeout: time.Minute,
 			})
 
-			apiLn, err := net.Listen("tcp", cfg.Listen)
-			if err != nil {
-				return fmt.Errorf("listening on %s: %w", cfg.Listen, err)
-			}
-			if cfg.MaxConnections > 0 {
-				// Past this, new connections wait in the kernel's backlog
-				// rather than each taking a goroutine and its buffers.
-				apiLn = netutil.LimitListener(apiLn, cfg.MaxConnections)
-			}
-			adminLn, err := net.Listen("tcp", cfg.AdminListen)
-			if err != nil {
-				_ = apiLn.Close()
-				return fmt.Errorf("listening on %s: %w", cfg.AdminListen, err)
-			}
-
 			// A metrics-only listener, when one is configured. Started after
 			// AdminHandler, which is where the registry it serves is built.
 			var metricsSrv *http.Server

internal/cli/server_args_test.go

@@ -0,0 +1,39 @@
+package cli
+
+import (
+	"context"
+	"net"
+	"strings"
+	"testing"
+	"time"
+)
+
+// `llmgw server check` once ran a whole second server: words after server
+// that name no subcommand are refused.
+func TestServerTakesNoWordsItDoesNotKnow(t *testing.T) {
+	cmd := newServerCmd()
+	cmd.SetArgs([]string{"check", "--config", "/nonexistent"})
+	cmd.SilenceUsage, cmd.SilenceErrors = true, true
+	if err := cmd.Execute(); err == nil || !strings.Contains(err.Error(), "unknown command") {
+		t.Errorf("err %v", err)
+	}
+}
+
+// A second server whose port is taken stops at once, before the router or
+// any control plane is built.
+func TestAServerWhosePortIsTakenStopsFirst(t *testing.T) {
+	taken, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer taken.Close()
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	cmd := newServerCmd()
+	cmd.SetArgs([]string{"--listen", taken.Addr().String(), "--admin-listen", "127.0.0.1:0",
+		"--endpoint", "a=http://127.0.0.1:1=m"})
+	cmd.SilenceUsage, cmd.SilenceErrors = true, true
+	if err := cmd.ExecuteContext(ctx); err == nil || !strings.Contains(err.Error(), "listening on") {
+		t.Errorf("err %v", err)
+	}
+}

internal/cli/serverinit.go

@@ -57,10 +57,12 @@ WantedBy=multi-user.target
 // it again finishes an install that stopped halfway and changes nothing on
 // one that did not.
 type serverInit struct {
-	etcDir   string // /etc/llmgw
-	stateDir string // /var/lib/llmgw
-	pkiDir   string // where the authority lives
-	unitPath string // "" leaves systemd alone
+	// serviceActive says whether llmgw-server runs; nil asks systemctl.
+	serviceActive func() bool
+	etcDir        string // /etc/llmgw
+	stateDir      string // /var/lib/llmgw
+	pkiDir        string // where the authority lives
+	unitPath      string // "" leaves systemd alone
 
 	// user owns the state and reads the key; "" means no user is created and
 	// nothing is chowned, which is what a test wants.
@@ -80,6 +82,16 @@ type serverInit struct {
 	// setup screen does with the password it was given; when set, patroni
 	// only names them.
 	patroniNodes []pgha.Node
+	// judgeMachines are machines for the guardrails' judges alone, added as
+	// nodes labelled for them; judgeCPUs their cores, once added.
+	judgeMachines []judgeMachine
+	judgeCPUs     []int
+	// secondMirror is which machine of the store, 1 or 2, keeps a second
+	// mirror in step with this machine's; 0 is none.
+	secondMirror int
+	// judgeNote is what timing the judge found, said before the next
+	// steps when it is not fine.
+	judgeNote string
 	// noMirror, noNode and noModel turn off the parts of a first install that
 	// make it serve something: a mirror, this machine as a node, and a small
 	// model on it.
@@ -234,6 +246,10 @@ func newServerInitCmd() *cobra.Command {
 	f.StringVar(&judgeCats, "judge-categories", strings.Join(defaultJudgeCategories, ","),
 		"what the judge refuses, comma-separated, of: "+strings.Join(judgeCategories, ", "))
 	f.IntVar(&in.judge.Replicas, "judge-replicas", 2, "how many copies of the judge run, each on CPUs")
+	f.IntVar(&in.secondMirror, "second-mirror", 0,
+		"with --patroni, a second mirror on the store's machine 1 or 2, kept in step with this one's (0: none)")
+	f.Var(judgeMachineFlag{&in.judgeMachines}, "judge-node",
+		"user@host of a machine for the guardrails' judges alone: added as a node, and the judges run only there; repeatable")
 	f.DurationVar(&in.judge.Budget, "judge-budget", 5*time.Second, "how long a request waits for the judge")
 	f.StringVar(&in.language, "language", "", "the portal's language for a browser that asks for neither: en or tr")
 	f.BoolVar(&in.signupOpen, "signup-open", false, "let anyone ask for an account on the portal, to be approved by an administrator")
@@ -257,6 +273,9 @@ func (in *serverInit) run(ctx context.Context) error {
 	if err := in.checkBundle(); err != nil {
 		return fmt.Errorf("offline bundle: %w", err)
 	}
+	if err := in.checkMemory(); err != nil {
+		return err
+	}
 	steps := []struct {
 		name string
 		fn   func(context.Context) error
@@ -317,6 +336,11 @@ func (in *serverInit) run(ctx context.Context) error {
 	if err := in.ensureWebhooks(ctx); err != nil {
 		fmt.Fprintf(in.out, "  !!    webhooks: %v\n", err)
 	}
+	if hasSystemd && len(in.judgeMachines) > 0 {
+		if err := in.ensureJudgeNodes(ctx); err != nil {
+			return fmt.Errorf("judge nodes: %w", err)
+		}
+	}
 	if in.judgeWanted() && in.configJudgesWith(guardModelName) {
 		// Not fatal: without its judge the baseline policy still checks for
 		// secrets and injection, and a judged request is served flagged.
@@ -338,6 +362,15 @@ func (in *serverInit) run(ctx context.Context) error {
 			return fmt.Errorf("standby control planes: %w", err)
 		}
 	}
+	if hasSystemd && in.secondMirror > 0 {
+		if err := in.ensureSecondMirror(ctx); err != nil {
+			// Not fatal: the first mirror serves; said, and how to try again.
+			fmt.Fprintf(in.out, "  !!    second mirror: %v; later: sudo llmgw mirror add-peer <user>@<machine>\n", err)
+		}
+	}
+	if hasSystemd && in.judgeWanted() && in.configJudgesWith(guardModelName) {
+		in.checkJudge(ctx)
+	}
 	in.nextSteps()
 	return nil
 }
@@ -345,12 +378,7 @@ func (in *serverInit) run(ctx context.Context) error {
 // judgeWanted is whether this install fetches the judge model, and so
 // whether the baseline policy asks it.
 func (in *serverInit) judgeWanted() bool {
-	if in.noGuardModel || (in.noMirror && in.mirrorURL == "") || in.unitPath == "" {
-		return false
-	}
-	// Offline, only a judge the bundle carries: a policy asking a judge
-	// that never comes refuses every request.
-	if in.bundle != "" && !in.bundleCarries(guardModelName) {
+	if !in.judgeComes() || in.unitPath == "" {
 		return false
 	}
 	_, err := exec.LookPath("systemctl")
@@ -902,6 +930,9 @@ func (in *serverInit) waitHealthy(ctx context.Context) error {
 }
 
 func (in *serverInit) nextSteps() {
+	if in.judgeNote != "" {
+		fmt.Fprint(in.out, "\n"+in.judgeNote)
+	}
 	fmt.Fprint(in.out, `
 The control plane is up. Next:
 
@@ -977,3 +1008,13 @@ func virtualInterface(name string) bool {
 	}
 	return false
 }
+
+// judgeComes is whether this setup has a judge to install: one not left
+// out, a mirror to fetch it from, and, offline, a bundle that carries it —
+// a policy asking a judge that never comes refuses every request.
+func (in *serverInit) judgeComes() bool {
+	if in.noGuardModel || (in.noMirror && in.mirrorURL == "") {
+		return false
+	}
+	return in.bundle == "" || in.bundleCarries(guardModelName)
+}

internal/cli/serverinit_choices.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"math"
 	"net"
+	"os"
+	"os/exec"
 	"path"
 	"slices"
 	"strconv"
@@ -11,6 +13,8 @@ import (
 	"time"
 
 	"gitea.mynodes.xyz/ilker/llmgw/internal/agent/provision"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/pgha"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/preflight"
 )
 
 // What a first install lets a person choose beyond which parts it has: which
@@ -154,6 +158,70 @@ func (s starterSpec) minMemoryGB() int {
 	return max(2, int(math.Ceil(s.SizeGB+1.5)))
 }
 
+// servingMemoryMB is what this machine needs, beyond what the control plane
+// does, for the models it will serve itself: the starter's and the judges'
+// reservations, and a gigabyte more because the scheduler counts a machine's
+// memory in whole gigabytes, rounded down — 7.75 GB is 7. Zero when it serves
+// none of them; what names those it does.
+//
+// Asked before anything is installed: the 8 GB machine the guide was first
+// recorded on finished every step and then had no room for the starter, the
+// one thing a person asks first.
+func (in *serverInit) servingMemoryMB(judgesElsewhere bool) (mb int, what string) {
+	if in.noNode {
+		return 0, ""
+	}
+	gb := 0
+	var parts []string
+	if !in.noModel && (!in.noMirror || in.mirrorURL != "") {
+		gb += in.starterModelSpec().minMemoryGB()
+		parts = append(parts, "the starter model")
+	}
+	// Only judges that will be installed: none without a mirror to fetch
+	// them from, or from a bundle that does not carry one.
+	if !judgesElsewhere && in.judgeComes() {
+		n := in.judgeFor().Replicas
+		gb += n * judgeMemoryGB
+		parts = append(parts, fmt.Sprintf("%d judges", n))
+	}
+	if gb == 0 {
+		return 0, ""
+	}
+	return (gb + 1) * 1024, strings.Join(parts, " and ")
+}
+
+// checkMemory refuses, before anything is installed, a machine too small for
+// the models it would serve as well as the control plane.
+func (in *serverInit) checkMemory() error {
+	if in.unitPath == "" {
+		return nil // a development run, served by nothing
+	}
+	// Run again on a machine already serving — to change --host, say, as
+	// the docs advise — it installs no models it does not already serve. A
+	// first run that stopped half way is checked again: it still would.
+	if in.alreadyServing() {
+		return nil
+	}
+	meminfo, err := os.ReadFile("/proc/meminfo")
+	if err != nil {
+		return nil
+	}
+	total, ok := pgha.MemTotal(string(meminfo))
+	if !ok {
+		return nil
+	}
+	extra, what := in.servingMemoryMB(len(in.judgeMachines) > 0)
+	if extra == 0 {
+		return nil
+	}
+	have, need := int(total>>20), preflight.Needs[preflight.RoleControl].MemoryMB+extra
+	if have >= need {
+		return nil
+	}
+	return fmt.Errorf("memory: this machine has %d MB; the control plane and %s it would serve need %d. "+
+		"Give it more, or leave them off it: --no-model, --no-guard-model, or --no-node to serve models only on nodes added later", have, what, need)
+}
+
 // defaultContext is the context a client may use of the starter.
 const defaultContext = 4096
 
@@ -194,6 +262,9 @@ func (in *serverInit) judgeFor() judgeSpec {
 	}
 	if j.Replicas <= 0 {
 		j.Replicas = 2
+		if in.singleMachine() {
+			j.Replicas = 1
+		}
 	}
 	if j.Budget <= 0 {
 		j.Budget = 5 * time.Second
@@ -201,6 +272,14 @@ func (in *serverInit) judgeFor() judgeSpec {
 	return j
 }
 
+// singleMachine is an install where this machine is the only node there
+// will be, as far as init knows: a second judge replica there shares the
+// same cores and is lost with the same machine, so it buys nothing but
+// half the speed of each.
+func (in *serverInit) singleMachine() bool {
+	return !in.noNode && !in.standbys && len(in.patroni) == 0 && len(in.patroniNodes) == 0
+}
+
 // The configuration's limits, as init writes them unless told otherwise.
 const (
 	defaultRPM       = 60
@@ -314,6 +393,12 @@ func (in *serverInit) initFlags() []string {
 	for _, t := range in.patroni {
 		add("--patroni", t)
 	}
+	for _, m := range in.judgeMachines {
+		add("--judge-node", m.target)
+	}
+	if in.secondMirror > 0 {
+		add("--second-mirror", fmt.Sprint(in.secondMirror))
+	}
 	switch {
 	case in.mirrorURL != "":
 		add("--mirror", in.mirrorURL)
@@ -346,7 +431,10 @@ func (in *serverInit) initFlags() []string {
 	if in.noGuardModel {
 		add("--no-guard-model")
 	} else {
-		j, d := in.judgeFor(), (&serverInit{}).judgeFor()
+		// Against the defaults for an install of the same shape: one judge
+		// on one machine, two otherwise.
+		shape := serverInit{noNode: in.noNode, standbys: in.standbys, patroni: in.patroni, patroniNodes: in.patroniNodes}
+		j, d := in.judgeFor(), shape.judgeFor()
 		if j.Fail != d.Fail {
 			add("--judge-fail", j.Fail)
 		}
@@ -395,3 +483,15 @@ func shellWord(s string) string {
 	}
 	return "'" + strings.ReplaceAll(s, "'", `'\''`) + "'"
 }
+
+// alreadyServing reports whether this machine's gateway is set up and
+// running: a server.yaml, and its unit active.
+func (in *serverInit) alreadyServing() bool {
+	if _, err := os.Stat(in.configPath()); err != nil {
+		return false
+	}
+	if in.serviceActive != nil {
+		return in.serviceActive()
+	}
+	return exec.Command("systemctl", "is-active", "--quiet", "llmgw-server").Run() == nil
+}

internal/cli/serverinit_choices_test.go

@@ -183,12 +183,17 @@ func TestTheJudgesAndTheStarterShareTheCPUsRatherThanEachTakingAll(t *testing.T)
 		in             serverInit
 		judge, starter int
 	}{
-		{serverInit{cpus: 4}, 1, 2},
-		{serverInit{cpus: 8}, 2, 4},
-		{serverInit{cpus: 32}, 2, 8},
-		{serverInit{cpus: 2}, 1, 0}, // nothing left: the starter shares rather than fits nowhere
+		// One machine: one judge, on up to four cores; the starter has the rest.
+		{serverInit{cpus: 4}, 4, 0},
+		{serverInit{cpus: 8}, 4, 4},
+		{serverInit{cpus: 32}, 4, 8},
+		{serverInit{cpus: 2}, 2, 0},
 		{serverInit{cpus: 1}, 0, 0},
-		{serverInit{cpus: 4, noGuardModel: true}, 1, 4},
+		{serverInit{cpus: 4, noGuardModel: true}, judgeCores, 4}, // no judge: all for the starter
+		// Two asked for on one machine: two cores each, one each where two
+		// would not fit both.
+		{serverInit{cpus: 8, judge: judgeSpec{Replicas: 2}}, 2, 4},
+		{serverInit{cpus: 2, judge: judgeSpec{Replicas: 2}}, 1, 0},
 		{serverInit{cpus: 8, judge: judgeSpec{Replicas: 3}}, 2, 2},
 		{serverInit{cpus: 4, noNode: true}, 2, 0}, // on nodes not known yet
 	} {
@@ -197,12 +202,40 @@ func TestTheJudgesAndTheStarterShareTheCPUsRatherThanEachTakingAll(t *testing.T)
 			t.Errorf("%+v: judge %d starter %d, want %d %d", c.in, got.judge, got.starter, c.judge, c.starter)
 		}
 	}
-	m := guardModel("http://x/g.gguf", 2, 1)
-	if p := m.Profiles[0]; p.CPUCores != 1 || p.MinMemoryGB != 4 {
-		t.Errorf("judge profile: %d cores, %d GB", p.CPUCores, p.MinMemoryGB)
+	m := guardModel("http://x/g.gguf", 2, 1, nil)
+	if p := m.Profiles[0]; p.CPUCores != 1 || p.MinMemoryGB != 2 || !slices.Contains(p.Args, "--cache-ram") {
+		t.Errorf("judge profile: %d cores, %d GB, args %v", p.CPUCores, p.MinMemoryGB, p.Args)
 	}
 	s := starterModel(starterChoices[0], defaultContext, 2, "http://x/q.gguf", []string{"6000-24g"}, true)
 	if cpu := s.Profiles[len(s.Profiles)-1]; cpu.Name != "cpu" || cpu.CPUCores != 2 || s.Profiles[0].CPUCores != 0 {
 		t.Errorf("starter: GPU profile %d cores, CPU %+v", s.Profiles[0].CPUCores, cpu)
 	}
 }
+
+// A second judge on the same machine shares its cores and is lost with it:
+// one machine has one, more machines two.
+func TestOneMachineHasOneJudgeAndMoreHaveTwo(t *testing.T) {
+	for _, c := range []struct {
+		in   serverInit
+		want int
+	}{
+		{serverInit{}, 1},
+		{serverInit{noNode: true}, 2},
+		{serverInit{patroni: []string{"a@db1", "b@db2"}}, 2},
+		{serverInit{standbys: true}, 2},
+		{serverInit{judge: judgeSpec{Replicas: 3}}, 3},
+	} {
+		if got := c.in.judgeFor().Replicas; got != c.want {
+			t.Errorf("%+v: %d judges, want %d", c.in, got, c.want)
+		}
+	}
+	// The defaults are left out of the command; a choice against them is in.
+	ha := serverInit{noNode: true, patroni: []string{"a@db1", "b@db2"}, judge: judgeSpec{Replicas: 2}}
+	if f := strings.Join(ha.initFlags(), " "); strings.Contains(f, "--judge-replicas") {
+		t.Errorf("two judges on three machines named: %s", f)
+	}
+	one := serverInit{judge: judgeSpec{Replicas: 2}}
+	if f := strings.Join(one.initFlags(), " "); !strings.Contains(f, "--judge-replicas 2") {
+		t.Errorf("two judges on one machine not named: %s", f)
+	}
+}

internal/cli/serverinit_cluster.go

@@ -64,6 +64,9 @@ const agentUnit = `[Unit]
 Description=llmgw node agent
 After=network-online.target
 Wants=network-online.target
+# Never given up on: a new release that fails its first starts, or an upgrade
+# that restarts it twice in a minute, would otherwise leave the node off.
+StartLimitIntervalSec=0
 
 [Service]
 ExecStart=/usr/local/bin/llmgw agent --config /etc/llmgw/agent.yaml
@@ -123,10 +126,10 @@ func (in *serverInit) writeUnit(path, body string) (bool, error) {
 func (in *serverInit) mirrorUnit() string {
 	base := "http://" + net.JoinHostPort(in.reachableAddr(), "8081")
 	if in.standbys {
-		return mirrorUnitFor(in.mirrorRoot(), ":8082", base, in.mirrorAllow(),
+		return mirrorUnitFor(in.mirrorRoot(), ":8082", base, in.mirrorAllow(), nil,
 			"'llmgw server init'. Bytes on :8081 for every node; the\n# management API for the control planes only, whichever leads.")
 	}
-	return mirrorUnitFor(in.mirrorRoot(), mirrorAPI, base, nil,
+	return mirrorUnitFor(in.mirrorRoot(), mirrorAPI, base, nil, nil,
 		"'llmgw server init'. Bytes on :8081 for every node; the\n# management API on loopback only, for the control plane beside it.")
 }
 
@@ -154,11 +157,14 @@ func (in *serverInit) mirrorAllow() []string {
 
 // mirrorUnitFor is a mirror's systemd unit. allow is who, besides the
 // machine itself, may use the management API.
-func mirrorUnitFor(dir, apiListen, base string, allow []string, about string) string {
+func mirrorUnitFor(dir, apiListen, base string, allow, peers []string, about string) string {
 	exec := "/usr/local/bin/llmgw mirror serve --dir " + dir + " --listen :8081 --api-listen " + apiListen + " --base " + base
 	for _, a := range allow {
 		exec += " --api-allow " + a
 	}
+	for _, p := range peers {
+		exec += " --peer " + p
+	}
 	return `[Unit]
 Description=llmgw model mirror
 After=network-online.target
@@ -485,7 +491,7 @@ func starterModel(spec starterSpec, ctx, cores int, source string, gpuClasses []
 
 // guardModel is the judge's catalog entry: CPU only, so it takes no card from
 // the models people use, on whichever node has room; replicas copies of it.
-func guardModel(source string, replicas, cores int) catalog.Model {
+func guardModel(source string, replicas, cores int, selector map[string]string) catalog.Model {
 	return catalog.Model{
 		Name:        guardModelName,
 		Description: "The guardrails' judge: reads prompts and answers for unsafe content. Not offered to clients.",
@@ -496,10 +502,15 @@ func guardModel(source string, replicas, cores int) catalog.Model {
 		// judge that is not there refuses everything.
 		Scaling: catalog.Scaling{Min: replicas, Max: replicas},
 		Profiles: []catalog.Profile{{
-			// It uses about 3.2 GB with its context: reserving 2 filled nodes
-			// past their memory.
-			Name: "cpu", Engine: "llamacpp", Priority: 100, MinMemoryGB: 4, CPUCores: cores,
-			Args: []string{"--ctx-size", "8192"},
+			// About 1.6 GB with its context, which stays so with no prompt
+			// cache: llama.cpp keeps up to 8 GB of prompts by default, and a
+			// judge's, each a different text, are not asked again. With the
+			// cache one grew to 3.2 GB over a day of traffic; reserving 4 for
+			// that left a 7 GB machine room for only one of the two.
+			Name: "cpu", Engine: "llamacpp", Priority: 100, MinMemoryGB: judgeMemoryGB, CPUCores: cores,
+			Args: []string{"--ctx-size", "8192", "--cache-ram", "0"},
+			// The judge machines, when the install was given some.
+			NodeSelector: selector,
 		}},
 	}
 }
@@ -521,7 +532,8 @@ func (in *serverInit) ensureStarter(ctx context.Context) error {
 func (in *serverInit) ensureGuardModel(ctx context.Context) error {
 	return in.ensureServed(ctx, guardModelName, guardModelSource, guardModelVersion, false,
 		func(url string, _ []string) catalog.Model {
-			return guardModel(url, in.judgeFor().Replicas, in.cpuPlan().judge)
+			cores, selector := in.judgePlacement()
+			return guardModel(url, in.judgeFor().Replicas, cores, selector)
 		})
 }
 
@@ -716,14 +728,16 @@ type cpuSplit struct{ judge, starter int }
 // the starter on one 4-core control plane all ran on all four: under load
 // most judgments missed their budget and the requests were refused.
 //
-// When this machine is the node, by its own CPUs: a core a judge under 8,
-// two from 8, and the starter what is left, up to 8, or no reservation at
-// all when nothing is, rather than a starter that fits nowhere. Otherwise
-// two a judge, on whichever node takes it, and the starter, on a node not
-// known yet, none.
+// A judge needs cores: a judgment of about 280 tokens took 8.0 s on one,
+// 4.2 s on two and 2.3 s on four, against a 5 s budget. On one machine its
+// one replica gets up to four; where there are two, two each (one each only
+// where two would not fit both). The starter has what is left, up to 8, or
+// no reservation at all when nothing is, rather than a starter that fits
+// nowhere. A machine that is not the node reserves two a judge on whichever
+// node takes it, and the starter, on a node not known yet, none.
 func (in *serverInit) cpuPlan() cpuSplit {
 	if in.noNode {
-		return cpuSplit{judge: 2}
+		return cpuSplit{judge: judgeCores}
 	}
 	n := in.cpus
 	if n <= 0 {
@@ -736,13 +750,23 @@ func (in *serverInit) cpuPlan() cpuSplit {
 	if !in.noGuardModel {
 		judges = in.judgeFor().Replicas
 	}
-	judge := 1
-	if n >= 8 {
-		judge = 2
-	}
-	left := n - judges*judge
-	if left < 1 {
-		left = 0
+	judge := judgeCores
+	switch {
+	case judges == 1:
+		judge = min(n, judgeCoresAlone)
+	case judges > 0 && judges*judge > n:
+		judge = max(1, n/judges)
 	}
+	left := max(n-judges*judge, 0)
 	return cpuSplit{judge: judge, starter: min(left, 8)}
 }
+
+// judgeCores and judgeMemoryGB are what a judge replica needs: two cores
+// for a judgment within its budget, and 2 GB for its 1.6 with no prompt
+// cache. judgeCoresAlone is what the one judge of a single machine takes,
+// past which a model this small hardly gets faster.
+const (
+	judgeCores      = 2
+	judgeCoresAlone = 4
+	judgeMemoryGB   = 2
+)

internal/cli/serverinit_cluster_test.go

@@ -171,7 +171,7 @@ func TestTheInstalledConfigurationIsHardenedAndLoads(t *testing.T) {
 }
 
 func TestTheGuardModelIsAValidJudge(t *testing.T) {
-	m := guardModel("http://10.0.0.5:8081/qwen3guard-0.6b/guard/g.gguf", 2, 2)
+	m := guardModel("http://10.0.0.5:8081/qwen3guard-0.6b/guard/g.gguf", 2, 2, nil)
 	c, err := catalog.New([]catalog.Model{m})
 	if err != nil {
 		t.Fatalf("not a valid catalog entry: %v", err)

internal/cli/serverinit_judges.go

@@ -0,0 +1,150 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"gitea.mynodes.xyz/ilker/llmgw/internal/control/adminapi"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/control/placement"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/onboard"
+	"gitea.mynodes.xyz/ilker/llmgw/internal/settings"
+)
+
+// Machines of the judges' own. Under load on a 4-core control plane that was
+// also a node, 38 of 60 requests were refused for want of a judgment; with the
+// judges on a node of their own the same test refused 2. A judge machine is
+// added as a node carrying judgeRoleLabel, and the judge's profile selects
+// that label, so nothing else is placed beside it and it on nothing else.
+
+// judgeRoleLabel marks a node as the judges'.
+const (
+	judgeRoleLabel = placement.RoleLabel
+	judgeRoleValue = "judge"
+)
+
+// judgeMachine is a machine for the judges: user@host, and the connection the
+// setup screen already made to it, when it made one.
+type judgeMachine struct {
+	target string
+	remote onboard.Remote
+}
+
+// ensureJudgeNodes adds each judge machine as a node labelled for the
+// judges, and says how many cores the smallest of them has.
+func (in *serverInit) ensureJudgeNodes(ctx context.Context) error {
+	if len(in.judgeMachines) == 0 {
+		return nil
+	}
+	na := nodeAdd{serverCfg: in.configPath(), plain: true}
+	na.opts.PKI = in.pkiDir
+	na.opts.NoFirewall = in.noFirewall
+	if err := na.prepare(); err != nil {
+		return err
+	}
+	in.judgeCPUs = nil
+	for _, jm := range in.judgeMachines {
+		o := na.target(jm.target)
+		fmt.Fprintf(in.out, "  ..    adding %s as a node for the judges\n", o.Addr)
+		r := onboard.New(o, nil)
+		if jm.remote != nil {
+			r.Remote = jm.remote
+		}
+		res, err := r.Run(ctx)
+		if err != nil {
+			return fmt.Errorf("%s: %w", o.Addr, err)
+		}
+		if err := na.watch(ctx, res.Node, func(onboard.Event) {}); err != nil && err != errNoAdmin {
+			return fmt.Errorf("%s: %w", res.Node, err)
+		}
+		if out, err := r.Remote.Run(ctx, "nproc", nil); err == nil {
+			if n, err := strconv.Atoi(strings.TrimSpace(string(out))); err == nil {
+				in.judgeCPUs = append(in.judgeCPUs, n)
+			}
+		}
+		if _, err := changeStoredSettings(in.configPath(), "a node for the judges, from init", func(doc *settings.Doc) error {
+			return doc.SetYAML([]string{"agents", "nodes", res.Node, "labels", judgeRoleLabel}, judgeRoleValue)
+		}); err != nil {
+			return fmt.Errorf("labelling %s for the judges: %w", res.Node, err)
+		}
+		in.done("%s is a node for the judges alone (%s: %s)", res.Node, judgeRoleLabel, judgeRoleValue)
+	}
+	return nil
+}
+
+// judgePlacement is the judge's cores and where it may run: on the judge
+// machines when there are some, by init's rule over their cores; otherwise
+// on any node, with this machine's plan.
+func (in *serverInit) judgePlacement() (cores int, selector map[string]string) {
+	if len(in.judgeMachines) == 0 {
+		return in.cpuPlan().judge, nil
+	}
+	return refitCores(in.judgeFor().Replicas, in.judgeCPUs), map[string]string{judgeRoleLabel: judgeRoleValue}
+}
+
+// judgeMachineFlag is --judge-node, given again for each machine.
+type judgeMachineFlag struct{ to *[]judgeMachine }
+
+func (f judgeMachineFlag) String() string {
+	if f.to == nil {
+		return ""
+	}
+	var out []string
+	for _, m := range *f.to {
+		out = append(out, m.target)
+	}
+	return strings.Join(out, ",")
+}
+
+func (f judgeMachineFlag) Set(v string) error {
+	if strings.TrimSpace(v) == "" {
+		return fmt.Errorf("--judge-node wants user@host")
+	}
+	*f.to = append(*f.to, judgeMachine{target: strings.TrimSpace(v)})
+	return nil
+}
+
+func (judgeMachineFlag) Type() string { return "user@host" }
+
+// judgeReadyWait is how long init waits for its judge to load before timing
+// it: the weights come from the mirror, and llama.cpp loads in seconds.
+const judgeReadyWait = 15 * time.Minute
+
+// checkJudge times the judge once it is up, and keeps what it found for the
+// closing text: a machine too slow for its judge is said before its first
+// refused request, not after. The budget is not changed without asking.
+func (in *serverInit) checkJudge(ctx context.Context) {
+	c := in.adminAPI()
+	deadline := time.Now().Add(judgeReadyWait)
+	for {
+		var judges []adminapi.JudgeView
+		if err := c.get(ctx, "/api/v1/guard/judges", &judges); err == nil {
+			ready := false
+			for _, j := range judges {
+				ready = ready || (j.Model == guardModelName && j.Ready > 0)
+			}
+			if ready {
+				break
+			}
+		}
+		if time.Now().After(deadline) || ctx.Err() != nil {
+			in.judgeNote = "  !!    the judge was not up to be timed; once it is: llmgw ctl guard judge check\n"
+			return
+		}
+		time.Sleep(10 * time.Second)
+	}
+	fmt.Fprintf(in.out, "  ..    timing the judge\n")
+	v, err := checkJudge(ctx, c, guardModelName, 0)
+	if err != nil {
+		in.judgeNote = "  !!    the judge could not be timed (" + err.Error() + "); later: llmgw ctl guard judge check\n"
+		return
+	}
+	if v.Verdict == "ok" {
+		in.done("the judge reads a prompt in %.1f s, of the %.1f s a request waits; about %.1f requests a second",
+			float64(v.SlowestMs)/1000, float64(v.BudgetMs)/1000, v.PerSecond/2)
+		return
+	}
+	in.judgeNote = "The judge is " + v.Verdict + " on this cluster:\n" + indent(judgeCheckText(v), "  ") + "\n"
+}

internal/cli/serverinit_judges_test.go

@@ -0,0 +1,67 @@
+package cli
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestJudgesGoOnTheirOwnMachinesWhenTheInstallHasSome(t *testing.T) {
+	in := newDefaultServerInit()
+	if _, sel := in.judgePlacement(); sel != nil {
+		t.Errorf("no judge machines, yet a selector: %v", sel)
+	}
+	if err := (judgeMachineFlag{&in.judgeMachines}).Set("ubuntu@10.0.0.21"); err != nil {
+		t.Fatal(err)
+	}
+	_ = (judgeMachineFlag{&in.judgeMachines}).Set("ubuntu@10.0.0.22")
+	in.judge.Replicas, in.judgeCPUs = 2, []int{4, 4}
+	cores, sel := in.judgePlacement()
+	if sel[judgeRoleLabel] != judgeRoleValue || cores != refitCores(2, []int{4, 4}) {
+		t.Errorf("cores %d, selector %v", cores, sel)
+	}
+	m := guardModel("http://x/g.gguf", 2, cores, sel)
+	if m.Profiles[0].NodeSelector[judgeRoleLabel] != judgeRoleValue {
+		t.Errorf("the judge's profile does not select its machines: %+v", m.Profiles[0])
+	}
+	// The same from a script.
+	flags := strings.Join(in.initFlags(), " ")
+	if !strings.Contains(flags, "--judge-node ubuntu@10.0.0.21") || !strings.Contains(flags, "--judge-node ubuntu@10.0.0.22") {
+		t.Errorf("flags %s", flags)
+	}
+	if err := (judgeMachineFlag{&in.judgeMachines}).Set(" "); err == nil {
+		t.Error("an empty --judge-node was taken")
+	}
+}
+
+func TestTheSetupAsksForJudgeMachinesWhenChosen(t *testing.T) {
+	m := newSetupModel("ctl", []string{"10.0.0.5"})
+	m.choice, m.page = 1, pMachines
+	m.mfocus = m.shown() * mfCount // the judges' choice
+	m = press(m, "right").(setupModel)
+	if m.judges != 1 || m.shown() != 3 || m.mfocus != 3*mfCount {
+		t.Fatalf("judges %d, shown %d, focus %d", m.judges, m.shown(), m.mfocus)
+	}
+	if v := m.machinesView(); !strings.Contains(v, "Judge machine 1") || !strings.Contains(v, "Check the 4 machines") {
+		t.Errorf("the page lacks the judge machine:\n%s", v)
+	}
+	for i, addr := range []string{"10.0.0.11", "10.0.0.12", ""} {
+		m.db[i].addr.SetValue(addr)
+		m.db[i].user.SetValue("ubuntu")
+		m.db[i].auth = authAgent
+	}
+	if err := m.validateMachines(); !strings.Contains(err, "judge machine 1 has no address") {
+		t.Errorf("err %q", err)
+	}
+	m.db[2].addr.SetValue("10.0.0.21")
+	if err := m.validateMachines(); err != "" {
+		t.Errorf("err %q", err)
+	}
+	if cmd := m.command(); !strings.Contains(cmd, "--judge-node ubuntu@10.0.0.21") || strings.Contains(cmd, "--patroni ubuntu@10.0.0.21") {
+		t.Errorf("command %s", cmd)
+	}
+	// None again: the judge machine is no longer asked for.
+	m = press(m, "left").(setupModel)
+	if m.judges != 0 || strings.Contains(m.machinesView(), "Judge machine 1") {
+		t.Errorf("judges %d after choosing none", m.judges)
+	}
+}