ilkerandClaude Opus 5
2373726efd
One bidirectional connect-go stream per node, carrying registration, heartbeats and shard status up, and start, stop and drain down. The agent dials out: GPU nodes sit behind firewalls far more often than a control plane does, and an outbound connection needs no inbound rule on every node in the fleet. - registration carries the whole hardware inventory, so there is no separate discovery call and a reconnecting agent refreshes what the scheduler knows. The fabric labels travel with it; they cannot be inferred from the wire, so losing them in transit would silently disable multi-node placement. - agentsvc is both the stream handler and the reconciler's dispatcher, because it holds the open streams and is therefore the only thing that can deliver a command to a node. - the agent validates a profile before launching anything, since an engine that refuses a profile does so after minutes of loading, then supervises the process and reports every transition with the engine's output tail on failure. - reconnects forever with jittered backoff. A control plane restart must not require touching every GPU node, and a fleet must not reconnect in lockstep and knock it over again. Engines keep serving throughout, because the router talks to them directly. llmgw agent is real now, and llmgw server runs a control plane whenever any model declares a profile. The static endpoint list stays for router-only runs. Verified with real binaries as separate processes: the agent registers, a replica is placed, an engine launches through the vLLM adapter's actual argument construction, streaming traffic is served, and killing the agent moves the node through unreachable to lost with placement explaining why nothing can run. config.Model and catalog.Model were the same thing described twice, so the router now reads catalog entries directly and the validation rules live in one place. Still missing: mTLS. The stream is plaintext HTTP/2 and must stay on a trusted network until that lands. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
64 lines
2.2 KiB
YAML
64 lines
2.2 KiB
YAML
# llmgw agent configuration, one per GPU node.
|
|
#
|
|
# The agent dials out to the control plane and keeps one stream open. Engines
|
|
# keep serving if the agent restarts: the router talks to them directly, and
|
|
# orphan adoption picks them up again on the next start.
|
|
|
|
node_id: gpu-a-01 # defaults to the hostname
|
|
server: "http://llmgw-server.internal:7443"
|
|
|
|
# The address engines are reachable on, and the address NCCL bootstraps over.
|
|
# Never a fabric address: NCCL rendezvouses over TCP before moving to RDMA.
|
|
mgmt_addr: "10.0.0.11"
|
|
mgmt_interface: eth0
|
|
|
|
labels:
|
|
rack: r12
|
|
|
|
heartbeat_interval: 5s
|
|
reconnect_base: 1s
|
|
reconnect_max: 30s
|
|
|
|
# Fabric labelling is explicit and there is no way around it. OpenSM's default
|
|
# subnet prefix is fe80:: on every fabric, so a matching prefix proves nothing
|
|
# and a wrong guess produces a replica that starts, passes health checks and
|
|
# then hangs on its first all-reduce (plan §5.2).
|
|
#
|
|
# A node with no fabrics is its own single-node island: it can host single-node
|
|
# replicas and will never be given a multi-node one.
|
|
fabrics:
|
|
- name: ib-a
|
|
hcas: [mlx5_0, mlx5_1, mlx5_2, mlx5_3]
|
|
rate_gbps: 200
|
|
|
|
discovery:
|
|
# Worth setting where the driver lives outside the default paths, which
|
|
# containerized driver installs often do.
|
|
nvidia_smi: ""
|
|
ib_root: /sys/class/infiniband
|
|
# NVML is the only source of NVLink topology, which is what keeps a
|
|
# tensor-parallel group off the PCIe path inside a node. It needs a binary
|
|
# built with `-tags nvml`; otherwise this silently falls back to nvidia-smi.
|
|
prefer_nvml: true
|
|
skip_gpus: false
|
|
|
|
engines:
|
|
vllm:
|
|
bin: /opt/venvs/vllm/bin/vllm
|
|
# Which multi-node mechanism works depends on the vLLM version, and the
|
|
# flags have changed more than once. Check the version you deploy.
|
|
launch_mode: ray # "ray" or "mp"
|
|
ray_bin: /opt/venvs/vllm/bin/ray
|
|
sglang:
|
|
# SGLang is launched as a module, which is its documented entry point.
|
|
python: /opt/venvs/sglang/bin/python
|
|
|
|
supervisor:
|
|
work_dir: /var/lib/llmgw-agent
|
|
# Engine output is the only diagnosis when a model fails to load, so keep a
|
|
# useful tail of it.
|
|
log_lines: 512
|
|
# Engines need time to free GPU memory cleanly before being killed.
|
|
stop_timeout: 60s
|
|
health_interval: 2s
|