Rollcall

Rollcall is a small, self-contained commissioning service for bare-metal servers, in the spirit of MAAS enlistment and commissioning, without the rest of MAAS.

A server that PXE-boots for the first time gets an ephemeral Debian live image. The image takes a full hardware inventory (DMI, DIMMs, CPUs, disks, NVMe, NICs, InfiniBand HCAs, GPUs, PCI, LLDP neighbours, TPM), creates an administrator account on the server's BMC through in-band IPMI, reports everything to the Rollcall server and powers the machine off. From then on the server is known: it shows up in the web UI and the CLI, its BMC can be driven through the API, and it will not boot the commissioning image again unless you ask for it.

Everything server-side is one static Go binary: HTTP API, embedded web UI, CLI, PostgreSQL schema management and the PXE bookkeeping.

How it works

unknown server ──PXE──▶ dnsmasq (DHCP+TFTP) ──▶ pxelinux default menu
                                                  │ 8 s timeout
                                                  ▼
                               Debian live image over HTTP (kernel+initrd via TFTP,
                               squashfs via HTTP, runs entirely from RAM)
                                                  │
                      rollcall-agent: inventory + BMC user + POST /api/v1/commission
                                                  │
                     rollcall server: PostgreSQL ◀─┘──▶ writes pxelinux.cfg/01-<mac>
                                                       (next boot: "commissioned → power off")

• Enlist: a machine is identified by its DMI system UUID (fallback: serial, then boot MAC). First contact creates it in state new.
• Commission: the inventory upload moves it to ready. The BMC password the agent generated is sealed with AES-256-GCM (key in /etc/rollcall/master.key) before it touches the database. It never leaves the server again: power and boot-device operations run ipmitool server-side.
• Re-commission: removes the per-MAC PXE override; optionally sets bootdev=pxe and power-cycles the machine through its BMC.

Repository layout

Path	What
cmd/rollcall/	Go server + CLI + embedded web UI (web/)
agent/	rollcall-agent.py (runs inside the live image), its systemd unit, build-image.sh (live-build recipe)
deploy/	install.sh, rollcall.service, config.example.json, pxelinux-default, os-sources.json, sync/dnsmasq/controller units, overlays/
images/	stateless root image recipes (build-rootfs.sh, compute-debian13/)
lab/	Proxmox test lab: pve-vbmc (virtual IPMI BMC for VMs backed by the Proxmox API), cloud-init for the PXE server VM
site/	Project website (static)
.gitea/workflows/	CI (fmt/vet/build/tests), release on tags, deploy on push to main

Server

# build
cd cmd/rollcall && CGO_ENABLED=0 go build -trimpath -ldflags="-s -w" -o rollcall .

# PostgreSQL role + database
sudo -u postgres psql -c "CREATE ROLE rollcall LOGIN PASSWORD '...';" -c "CREATE DATABASE rollcall OWNER rollcall;"

# config (see deploy/config.example.json), tokens from `rollcall keygen`
sudo install -d -m 0750 /etc/rollcall && sudo install -m 0640 config.json /etc/rollcall/config.json

# install binary, systemd unit, pxelinux menu, tftp symlinks
cd deploy && sudo ./install.sh

config.json keys: listen, image_dir (served under /rollcall/), tftp_root, database_url, master_key_file, admin_token (web UI + management API), agent_token (what the live image presents), commission_append (kernel command line baked into generated PXE files), bmc_hints (out-of-band BMC mapping for machines without in-band IPMI, e.g. VMs).

CLI (same binary)

rollcall list
rollcall show m-2ef1dab828c8 [-json]
rollcall events m-2ef1dab828c8
rollcall power m-2ef1dab828c8 status|on|off|soft|cycle|reset
rollcall bootdev m-2ef1dab828c8 pxe|disk|cdrom|bios|none
rollcall recommission m-2ef1dab828c8 [-now]
rollcall delete m-2ef1dab828c8

Reads ROLLCALL_URL / ROLLCALL_TOKEN, or the config file when readable.

API

Method	Path	Auth	Purpose
POST	/api/v1/commission	agent token	inventory upload from the live image
GET	/api/v1/bmc-hint?macs=	agent token	out-of-band BMC hint for VMs
GET	/api/v1/machines	admin	list (summaries)
GET	/api/v1/machines/{id}	admin	full record: inventory, BMC (no secret), events
POST	/api/v1/machines/{id}/power	admin	{"action":"on"} etc., runs ipmitool server-side
POST	/api/v1/machines/{id}/bootdev	admin	{"device":"pxe"}
POST	/api/v1/machines/{id}/recommission[?now=1]	admin	boot the image again on next PXE (now=1: via BMC immediately)
DELETE	/api/v1/machines/{id}	admin	forget the machine
GET/POST/DELETE	/api/v1/profiles[/{name}]	admin	stateless profiles
POST	/api/v1/machines/{id}/assign /unassign	admin	stateless node assignment
GET	/api/v1/os	admin	OS image catalog
POST	/api/v1/machines/{id}/deploy	admin	{"os":"rocky-9","disk":"/dev/sda","hostname":"","package_upgrade":false,"boot":true}
POST	/api/v1/machines/{id}/release	admin	wipe job
GET / POST	/api/v1/machines/{id}/jobs[/cancel]	admin	job history / cancel
GET	/api/v1/jobs/self, POST …/progress	job token (X-Rollcall-Job)	deploy agent
POST	/api/v1/phone-home/{token}	job token in path	cloud-init phone_home
GET	/os/*	none	OS disk images
GET	/rollcall/*	none	image files (kernel, initrd, squashfs)
GET	/	token in browser	web UI

Admin auth is Authorization: Bearer <admin_token>; the agent sends X-Rollcall-Token.

Commissioning image

agent/build-image.sh builds a Debian 13 live image with live-build (about 8 minutes, ~780 MB squashfs). It contains the full Debian kernel with non-free firmware, ipmitool, freeipmi, rdma-core, infiniband-diags, mstflint, nvme-cli, smartmontools, lldpd, lshw and an SSH server (root, key only) for debugging. Output goes to image_dir.

Kernel parameters understood by the agent: rollcall.server=URL (required), rollcall.token=…, rollcall.bmcuser=NAME (default commissioner), rollcall.nopoweroff (stay up after reporting).

BMC account

In-band (/dev/ipmi0): find the LAN channel, pick the existing commissioner slot or the first empty user ID ≥ 3, set name/password, ADMINISTRATOR privilege, channel access, enable, SOL payload. The password is random (16 chars) and is reported once to the server. If no in-band IPMI exists the agent asks the server for a hint (bmc_hints) and verifies it out-of-band.

Vendor quirks (iDRAC/iLO password policies, missing empty slots) are reported in bmc.errors and visible in the UI.

Stateless nodes (Warewulf-style)

For HPC compute nodes Rollcall can boot a root image straight into RAM and dress it with per-node files, instead of installing an OS on disk.

• Images live in images_dir/<name>/{vmlinuz,initrd.img,filesystem.squashfs} and are built with images/build-rootfs.sh <name> from images/<name>/{packages.list,hook.chroot,includes/} (live-build, same toolchain as the commissioning image). images/compute-debian13 is a Debian 13 compute node: slurmd, munge, rdma-core, NFS client, firmware.
• Profiles bind an image to overlays, extra kernel parameters, a node name format (node%03d) and variables: rollcall profile add compute -image compute-debian13 -overlays compute.
• Assigning a commissioned machine to a profile allocates a node name and IPs from node_pools, writes a per-MAC PXE entry that boots the image with hostname=, rollcall.server= and a per-node token, and exports static DHCP leases plus host names for dnsmasq (dnsmasq_dir, re-read on HUP via rollcall-dnsmasq.path). rollcall assign <id> compute -boot also power-cycles the machine through its BMC.
• Overlays are directory trees under overlays_dir/<overlay>/{system,runtime}; files ending in .tmpl are Go templates rendered with the node, all nodes of the cluster, the profile and cluster_vars. The compute overlay generates /etc/hosts, slurm.conf (node lines from the commissioning inventory: sockets, cores, threads, memory, GPUs), gres.conf, a persistent SSH host key per node (sealed in the database), root authorized_keys and the munge key. Inside the image rollcall-overlay.service applies the system overlay before munge/slurmd/ssh start; a timer refreshes the runtime overlay every five minutes, which doubles as the node heartbeat (booted state, last seen).
• The controller renders the same files: rollcall render compute etc/slurm/slurm.conf > /etc/slurm/slurm.conf.

States: ready → stateless → booted; rollcall unassign releases name and IPs.

OS deployment (install to disk)

For nodes that should run an operating system from their own disk, Rollcall writes a vendor cloud image onto the disk and lets cloud-init do first-boot configuration. No installer, no kickstart/preseed: a deployment is a streamed disk write and takes about as long as the image download.

rollcall deploy <id> rocky-9 -boot -watch
   │ server: picks the disk (smallest that fits, or -disk), allocates hostname + IP,
   │         creates a job with a one-time token, writes pxelinux.cfg/01-<mac>
   │         ("deploy" entry = commissioning image with rollcall.mode=deploy), power-cycles via BMC
   ▼
commissioning image, deploy mode (agent/rollcall-deploy.py)
   GET /api/v1/jobs/self        → image URL, sha256, disk, rendered cloud-init seed
   curl | tee sha256 | pv | zstd -d | dd of=/dev/sda      (progress every 3 s)
   mount root fs → /var/lib/cloud/seed/nocloud/{meta-data,user-data}, datasource_list: [NoCloud, None]
   (SELinux images: /.autorelabel; UEFI hosts: efibootmgr entry for the ESP loader)
   POST progress state=done  → server: state deployed, PXE entry = local disk, reboot
   ▼
first boot: cloud-init sets hostname/fqdn, SSH keys (root + default user), optional
package_upgrade, then phone_home → POST /api/v1/phone-home/<token> (shown as "phoned home")

Image catalog and freshness

os_dir/<name>/<version>/disk.raw.zst     raw disk image, zstd
os_dir/<name>/<version>/meta.json        sizes, sha256, upstream checksum, import time
os_dir/<name>/current -> <version>       what new deployments use

os_sources (deploy/os-sources.json) lists upstream "latest" URLs with the vendor checksum file for each: Debian 13, Ubuntu 24.04, Rocky 9, AlmaLinux 9, CentOS Stream 9. rollcall os sync fetches the checksum file, and only when the vendor checksum differs from every imported version does it download the image, verify it, convert to raw (qemu-img), compress, write a new version directory and flip current atomically. rollcall-os-sync.timer runs it nightly; keep versions are retained per source, nothing younger than a day is pruned, and a job always pins the exact version it started with. Sources with "track": "pinned" still download new versions but keep current until rollcall os promote <name> <version>. Local files go in with rollcall os import <name> <file.qcow2>. Image freshness is monthly at best upstream; the deploy option -upgrade (package_upgrade) pulls the rest on first boot.

rollcall os list | sync [NAME...] [-force] | import NAME FILE [-family debian|rhel] | promote NAME VERSION | rm NAME VERSION
rollcall deploy ID OS [-version V] [-disk /dev/nvme0n1] [-hostname H] [-upgrade] [-packages a,b] [-user-data FILE] [-boot] [-watch]
rollcall release ID [-wipe quick|full] [-boot] [-watch]     # wipe the disk, back to ready
rollcall jobs ID [-watch] | job cancel ID

States: ready → deploying → deployed (deploy-failed on error; the agent stays up for ssh). A deployed machine's PXE entry defaults to local disk, so boot order can stay "network first" on BIOS hosts; on UEFI hosts the agent adds a boot entry for the installed loader. rollcall recommission or release take it back.

Lab

lab/ documents a Proxmox SDN test setup: an isolated vnet, a PXE server VM running dnsmasq + Rollcall, two diskless VMs, and pve-vbmc, a tiny IPMI-over-LAN BMC emulator that drives VMs through the Proxmox API so that ipmitool power on and chassis bootdev pxe work against virtual machines.

Status

Commissioning, stateless nodes and disk deployment work end to end in the lab (virtual machines with 30 GB disks, SeaBIOS, out-of-band BMC hints). The in-band BMC path and the UEFI boot-entry step are implemented but have not yet been exercised on real hardware.