Files
serverAppConfigs/serverAppConfigs-docs/Infrastructure/Observability.md
T
Frank 650b6e0281 fix(observability): serve every exporter bind; scrape same-host cadvisor via gateway
Two shipped-2026-10-20 bugs that left gpu-dankclaw, gpu-dankserver and
cadvisor-dankclaw DOWN beside a green deploy:

- gpu-exporter.py built one ThreadingHTTPServer per bind but ran
  serve_forever() on servers[0] only: the LAN-class socket sat listen()ing
  but never accept()ed, loopback deploy gate passed, every scrape that
  reached the other bind timed out on the SYN backlog. Now one thread per
  extra bind. Regression test spins --serve on two loopback binds and
  requires BOTH to answer /metrics.

- cadvisor-dankclaw scraped its own host's LAN IP. Measured from inside the
  Prometheus container: a bridge container cannot dial its own host's LAN
  address at all (hairpin refuses published ports too); the podman gateway
  answers. Target moved to host.containers.internal:8080; the seam that
  pinned the LAN address (asserting the wrong doctrine) is re-pinned to the
  gateway plus a negative pin against the own-host LAN dial. Observability
  page records the measured reachability law replacing the inferred one.
2026-10-21 00:34:17 -07:00

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---
type: reference
title: "Observability on Dankclaw"
description: "The observability stack: what runs, how it is deployed, how it is exposed, and what is still unconfigured."
tags: [observability, prometheus, grafana, loki, alloy, node-exporter, gpu-exporter, quadlet, dankclaw]
timestamp: 2026-10-20
---
# Observability on Dankclaw
## Summary
Seven containers and two host-side processes: Prometheus (metrics), Grafana
(dashboards), Loki (log store), Alloy (log shipper), node-exporter (host
metrics), cadvisor (per-container metrics) and Alertmanager (alert delivery),
plus two host `python3` processes — `gpu-exporter` (per-GPU metrics) and `signal-relay` (Signal delivery). The containers are all Quadlet-managed,
boot-persistent and loopback-only, deployed by
`scripts/deploy-remote.sh` → `deploy_observability`. The metrics half works
end to end; the log half is configured, healthy, and carries no data.
This body was rewritten on 2026-10-18 from live evidence: the previous version
was deleted down to its front matter by commit `93d1181` (the "OKF v0.1
compliance pass"), while sibling pages kept pointing at a "state note" on this
page that no longer existed. Every statement below carries the command or file
that proves it today.
## The stack
| Service | Container | Published | Unit | Page |
|---|---|---|---|---|
| Prometheus | `docker.io/prom/prometheus:latest` | `127.0.0.1:9090` | `prometheus.container` | [[Prometheus]] |
| Alertmanager | `docker.io/prom/alertmanager:latest` | `127.0.0.1:9093` | `alertmanager.container` | [[Alertmanager]] |
| Grafana | `docker.io/grafana/grafana:latest` | `127.0.0.1:3002` → 3000 | `grafana.container` | [[Grafana]] |
| Loki | `localhost/franksdank/loki:latest` | `127.0.0.1:3100` | `loki.container` | [[Loki]] |
| Alloy | `localhost/franksdank/alloy:latest` | `127.0.0.1:12345` | `alloy.container` | [[Alloy]] |
| node-exporter | `docker.io/prom/node-exporter:latest` | host netns: `127.0.0.1:9100` + `192.168.0.143:9100` | `node-exporter.container` | [[Node-Exporter]] |
| cadvisor | `gcr.io/cadvisor/cadvisor:v0.49.1` | bridge publish `127.0.0.1:8080` + `192.168.0.143:8080` | `cadvisor.container` | — |
| GPU exporter | host `python3`, not a container | `127.0.0.1:9401` + host LAN `:9401` | `scripts/gpu-exporter.service` (user unit) | — |
| Signal relay | host `python3`, not a container | `192.168.0.143:18093` | `scripts/signal-relay.service` (user unit) | [[Alertmanager]] |
Every unit lives in `dankclaw/observability/quadlet/`, carries
`Restart=always`/`RestartSec=10` and `WantedBy=default.target`, is installed at
`~/.config/containers/systemd/<name>.container`, and reports `generated` +
`active` (`systemctl --user is-enabled|is-active` for all six, 2026-10-18;
linger is on for `dank`). `signal-relay.service` reports `enabled` + `active`
the same day, and `homepage-status.timer` — the root unit that probes all of
these on loopback — is `enabled` + `active` (`deploy-remote.sh:319-321` copies
the probe registry `shared/homepage/services.json` to `/srv/homepage`).
Dankserver runs the same family: node-exporter and cadvisor as its own quadlets
(`dankserver/observability/quadlet/{node-exporter,cadvisor}.container`,
`generated` + `active`; node-exporter binds `127.0.0.1:9100` + `192.168.0.235:9100`,
cadvisor publishes `127.0.0.1:8080` + `192.168.0.235:8080`), plus the host-process
`gpu-exporter` (a user unit installed the same way as `signal-relay`).
## Exposure
The five HTTP surfaces publish on `127.0.0.1` only — `ss -ltnp` (2026-10-18)
shows `127.0.0.1:9090`, `127.0.0.1:9093`, `127.0.0.1:3002`, `127.0.0.1:3100`
`127.0.0.1:12345` and no wildcard — because each of them is unauthenticated
inside, and several carry lifecycle or query APIs. Browser access goes through
Caddy: each vhost (`dankclaw/Caddyfile:128-145`) proxies to the guard
`anubis:8923`, and the post-auth handlers route by container name on
`dankclaw_default` — `loki.franksdank.cloud` → `loki:3100` (`:364-366`)
`grafana.franksdank.cloud` → `grafana:3000` (`:374-376`)
`prometheus.franksdank.cloud` → `prometheus:9090` (`:379-381`).
Alertmanager has no vhost at all. node-exporter is the exception that must live
in the host network namespace, and it binds exactly two addresses rather than
the wildcard — see [[Node-Exporter]].
**Same-host reachability from a bridge container is measured, not inferred**
(2026-10-21, from inside the Prometheus container): `host.containers.internal`
(the podman gateway) reaches host services whether they bind host-net or are
published ports — node `:9100`, cadvisor `:8080`, gpu `:9401` all answer there
— while the host's own LAN IP is refused (`192.168.0.143:8080`, `:9401`), so
every same-host Prometheus target uses the gateway and only cross-host targets
(dankserver) use plain LAN. Whether LAN works at all is network-specific: the
relay at `192.168.0.143:18093` IS reached from alertmanager's network, with
iptables INPUT admitting loopback, the host itself and the podman bridge subnet
`10.89.0.0/16` before the DROP (`scripts/deploy-remote.sh:255-262`). Never
point a scrape target at a host LAN IP from its own host on the strength of
one working example; dial the gateway and probe.
## Deployment
`./scripts/deploy.sh dankclaw --service <name>` runs `deploy_observability`
which installs the unit, copies that service's config
(`copy_prometheus_config`, `copy_alertmanager_config`, `copy_loki_config`
`copy_alloy_config`, `copy_grafana_provisioning`, plus
`install_signal_relay` with the alertmanager deploy), then waits on the loopback
health endpoint (`/prometheus`: `/-/healthy`, `/alertmanager`: `/-/healthy`
`/grafana`: `/api/health`, `/loki`: `/ready`, `/alloy`: `/-/healthy`
`/node-exporter`: `/metrics`). Startup order follows the data dependencies —
`grafana` after `prometheus`, `alloy` after `loki`
(`grafana.container:32-33`, `alloy.container:38-39`). See
[[Observability Provisioning]] for what is provisioned as code and how to
verify it through the APIs.
## Current state (2026-10-20)
* **Metrics: working.** `curl -s http://127.0.0.1:9090/api/v1/targets` reports
eight up targets — the three LLM endpoints (frank-archon on `vllm:*`,
frank-dragoon and frank-zealot on `llamacpp:*`), grafana, loki, prometheus
and both node exporters. The four downs are structural (the `comfyui` and
`services` HTML probes, and Gitea's disabled metrics endpoint), not outages.
Two rule groups in `shared/prometheus/rules/llm-fleet.yml`: `llm-fleet`
(2 recording + 4 alert, `llamacpp:*`) and `vllm-fleet` (1 recording + 4
alert, `vllm:*` — archon queueing, prefix collapse, preemption, p95
time-to-first-token), each keyed only to the namespace its runtime exports.
* **Delivery: working.** Alertmanager's single `signal` receiver webhooks the
relay, and `journalctl --user -u signal-relay` records successful
`sent to +12062476336:` lines for every rule in the set.
* **Dashboards: working.** Provisioned datasources — Prometheus (uid
`prometheus`) and Loki (uid `loki`) — and the `llm-fleet`, `host-system`,
`containers`, `observability` and `logs-overview` dashboards, all
installed from `shared/grafana/provisioning/`. The Loki datasource is how
you read logs: Loki has no web UI of its own, so Grafana Explore is the
human surface (the guarded `loki.franksdank.cloud` vhost serves only the API).
* **Per-container metrics: the `containers` dashboard (added 2026-10-20; live
after `deploy.sh <host> --service cadvisor`).** cadvisor is the only way to see
per-container CPU/memory here, and on this rootless-Podman host it works on one
condition: `--cgroupns=host`. Podman starts every container in a PRIVATE cgroup
namespace, so without that flag cadvisor sees only its own cgroup root and
exports a single series (measured 2026-10-20: 1 series off, 996 on). cadvisor
names nothing itself — the libpod socket resolved only 2 of 34 rootless
containers — but the quadlet unit name is carried in the cgroup path
(`app.slice/<name>.service/…`), so `prometheus.yml` relabels that path into a
`container` label. Network and filesystem are NOT exported for these containers
(no netns/classid attribution under the host-PID layout), so the dashboard
graphs only CPU, memory and OOM and does not fake the rest.
* **Per-GPU metrics: the `host-system` GPU panels (added 2026-10-20; live after
`deploy.sh <host> --service gpu-exporter`).** `scripts/gpu-exporter.py` is a
host-process user unit on BOTH hosts — not a quadlet, because it reads the host's
own DRM sysfs and shells to `nvidia-smi`, neither of which a container can do
without GPU passthrough. It reads each AMD card's `gpu_busy_percent` /
`mem_info_vram_*` / `hwmon temp1_input` and one `nvidia-smi --query-gpu` CSV, and
emits unified `gpu_*` families (utilization %, VRAM used/total bytes, temperature
°C, power W) labelled `gpu` / `vendor` / `model`, with `host` added by the scrape
job. Two laws: **absent means absent, never a zero** — the R9700s expose no sysfs
`power1_average`, so they carry no `gpu_power_watts` line at all (only NVIDIA and
the Dankclaw 8060S iGPU report power); and it binds loopback + the host LAN, like
node-exporter, never the wildcard. The dashboard graphs util/VRAM/VRAM-%/temp/power.
* **Logs: fixed in code, awaiting deploy.** The pipeline shipped nothing because
a rootless Alloy cannot read the `0640` journal files, and the container-log
globs point at a root-storage layout that does not exist here. The fix is built
and tested in-repo (2026-10-20): Alloy is now a **root system service on
`Network=host`**, reading `system.journal` + `user-*.journal` and pushing to
Loki's `127.0.0.1:3100` loopback publish — a throwaway root probe read 31,825
lines and pushed 26,966 with zero drops. The **live** instance is still the old
rootless unit until `deploy.sh dankclaw --service alloy` runs. Detail in
[[Alloy]] → Why root; Loki's store state in [[Loki]] → Contents.
* **Not configured:** no blackbox exporter (the structural downs have no real
uptime signal) and no Alertmanager vhost. The log pipeline's fix is in code but
not yet deployed (see *Logs* above).
## Citations
- `dankclaw/observability/quadlet/{prometheus,alertmanager,grafana,loki,alloy,node-exporter,cadvisor}.container`
- `scripts/deploy-remote.sh:219-300` (copiers + relay), `:521-536` (health waits), `:477-486` (grafana env seed)
- `scripts/signal-relay.py:26-49`, `scripts/signal-relay.service`
- `scripts/gpu-exporter.py`, `scripts/gpu-exporter.service` (per-GPU host exporter)
- `shared/prometheus/prometheus.yml`, `shared/prometheus/alertmanager.yml`, `shared/prometheus/rules/llm-fleet.yml`
- `shared/grafana/provisioning/`, `shared/loki/loki-config.yaml`, `shared/alloy/config.alloy`
- `tests/observability_quadlet.bats` (boot persistence, no wildcard publish, probe addresses, delivery contract)
- Host evidence 2026-10-18: `ss -ltnp`, `podman ps`, `systemctl --user is-enabled|is-active`, `curl` on `127.0.0.1:9090/api/v1/{targets,rules,alerts}`, `127.0.0.1:3100/loki/api/v1/labels`, `127.0.0.1:12345/metrics`, `127.0.0.1:3002/api/health`, `192.168.0.143:18093/health`, `journalctl --user -u signal-relay`