Per-container CPU/memory was invisible for the quadlet app stack — Grafana could
only see the host (node_exporter) and the LLM engines. This adds a rootless
cadvisor quadlet on each host and a `containers` dashboard.
cadvisor works on this rootless-Podman / cgroup-v2 host on one condition:
--cgroupns=host. Podman starts every container in a private cgroup namespace, so
without it cadvisor sees only its own cgroup root and exports a single series
(measured 2026-10-20: 1 series off, 996 on). The libpod socket does not name the
rootless app containers (it resolved 2 of 34), so naming comes from elsewhere:
the quadlet unit name is carried in the cgroup path
(app.slice/<name>.service/libpod-payload-<hex>), and Prometheus relabels it into
a `container` label. No podman socket needed.
cadvisor cannot bind per-interface like node_exporter, so each unit is a bridge
container publishing exactly 127.0.0.1:8080 and the host LAN address — never a
wildcard. Prometheus (a bridge container) reaches a host-published port at the
LAN address, so cadvisor-dankclaw/dankserver scrape 192.168.0.143:8080 /
192.168.0.235:8080. Only the families cadvisor actually exports for these
containers are graphed — CPU usage, memory working-set/limit, OOM — not network
or filesystem, which are absent under the host-PID layout.
Wired through the deployer (allowlist, deploy_observability case + /healthz gate,
dispatcher), the planner (both targets), and observability_quadlet.bats.
Dankserver's node-exporter has been dead since a reboot: `podman ps -a` showed
it `Exited (143)` and Prometheus' `node-dankserver` job has been scraping
nothing. It ran only from `dankserver/compose.yaml`, which is the failure mode
this repository's boot-persistence rule exists for (rootless Podman does not
restart bare containers after the stop that shutdown performs), and the compose
form bound the wildcard address — the unauthenticated-metrics-API-on-every-
interface posture already removed on Dankclaw.
- dankserver/observability/quadlet/node-exporter.container — mirrors the
Dankclaw unit, listening on exactly 127.0.0.1:9100 (host-local probes) and
192.168.0.235:9100 (Prometheus on Dankclaw), with Restart=always and
WantedBy=default.target.
- the compose service is deleted: one owner per container name.
- deploy_observability now installs from "$TARGET/observability/quadlet"; it
hardcoded the Dankclaw path, so a Dankserver unit could not be installed by
the shared dispatcher at all.
- planner: "node-exporter" joins the Dankserver service set, with a path rule
for dankserver/observability/**; the dispatcher's allowlist gains
dankserver:node-exporter.
Seams cover the silent halves: both listen addresses present and the wildcard
absent, the compose service gone, the allowlist entry present, and the planner
mapping the path to the service.