docs(decisions): record what the CI gate actually reported, not the tick

The PR's required check went green as "Successful in 1m40s" — a real run, not
"Has been skipped". But .gitea/workflows/gate.yml:138 is
`./ci/gate.sh || [ "$?" -eq 3 ]`, so a green tick means exit 0 OR 3 and cannot
distinguish them. Fetched the job log and read the gate's own headline:
MERGE GATE: UNDETERMINED, one stage that did not run (spec-immutability).

So CI is rc 3 too, and the tick is the tolerance swallowing it. Recorded that
plainly rather than leaving "CI green" to be read as rc 0.

Also corrects a claim that had gone stale within the same entry: CI ran two
stages my worktree run could not, and both passed — gitea-settings (the live
Gitea matches infra/gitea/expected-branch-protection.json; runners online 1)
and approval-policy with real PR context (no sensitive paths touched, so
infra/ansible/** needs no human reviewer). My local run skipped both, and the
handoff said branch protection was UNVERIFIED. It is now measured, so saying
otherwise would have left a known-false line in the log.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

decisions/2026-09-30-flux-deploy-notification-inhibited.md

@@ -0,0 +1,95 @@
+---
+date: 2026-09-30
+branch: fix/flux-deploy-notification-inhibited
+title: The deploy notification routed correctly and was then inhibited before sending — `severity: info` is a suppressed class in kube-prometheus-stack
+---
+
+## What changed
+
+`FluxRolloutInProgress` (shipped hours earlier in PR #25) fired correctly on the very first real
+deploy and **its mail was suppressed before Alertmanager sent it**. One label changed:
+
+- `platform/monitoring/alerts.yaml` — `FluxRolloutInProgress` now carries `notification: deploy` and
+  **no `severity` label at all**, where it previously carried `severity: info`.
+- `platform/monitoring/kube-prometheus-stack.yaml` — the deploy route matches
+  `notification = "deploy"` instead of `severity = "info"`. Receiver, subject and grouping unchanged.
+- `platform/monitoring/tests/flux-rollout.test.yaml` — the three `FluxRolloutInProgress` `exp_labels`
+  blocks updated. `FluxRolloutStuck` keeps `severity: warning` and is unaffected.
+
+**The mechanism, measured rather than reasoned about.** kube-prometheus-stack's `general.rules`
+ships:
+
+    InfoInhibitor:
+      group by (namespace) (ALERTS{severity="info"} == 1)
+        unless on (namespace) group by (namespace)
+          (ALERTS{alertname!="InfoInhibitor", alertstate="firing", severity=~"warning|critical"} == 1)
+
+which fires for any namespace holding a firing `severity="info"` alert **and nothing else wrong in
+it**. The chart's third `inhibit_rule` then drops exactly that alert:
+
+    source_matchers: [alertname="InfoInhibitor"]
+    target_matchers: [severity="info"]
+    equal:           [namespace]
+
+For a deploy notification this is the worst possible interaction, because the suppressed case is the
+*only* case that matters: on a healthy rollout of a healthy cluster, `flux-system` holds no warning
+or critical alert, so `InfoInhibitor` fires and the deploy mail is inhibited. It would have been
+delivered only when something else in `flux-system` was already broken.
+
+Upstream's intent is explicit and reasonable — `severity: info` means "only worth showing next to a
+real problem". A deploy notice is not that, so it must not claim that severity. `notification` is a
+label **no** `inhibit_rule` in the chart targets (all three match on severity values), and dropping
+`severity` also stops `InfoInhibitor` firing for `flux-system` at all rather than merely working
+around it. Both files carry the full reasoning inline, and `alerts.yaml`'s design header now names
+the severity label as a third thing that must not regress — "do not tidy this by adding a severity"
+— because the next reader's instinct will be to add one back.
+
+## What I verified
+
+Against live prod, after PR #25 merged as `64c72fd` and Flux converged:
+
+- **The metrics work.** `kube_flux_kustomization_info` 16, `kube_flux_kustomization_suspended` 16,
+  `kube_flux_gitrepository_info` 1 = **33 series, exactly as designed**. The `revision` label IS
+  populated (`main@sha1:296d6d3…` / `…64c72fd…`), so the `status.lastAppliedRevision` /
+  `status.artifact.revision` paths are correct — previously UNVERIFIED.
+- **The `podAnnotations` roll mechanism works.** The KSM pod carries
+  `homelab.keithjackson.dev/crs-config-rollout: 1` and is a new pod
+  (`…-7b56d98f46-56n8j`, replacing the 2026-09-19 one), so the config-only-change trap was
+  genuinely closed rather than merely documented.
+- **The rule works, in both directions.** It fired for **12** lagging Kustomizations while 4 had
+  converged (`count by (revision)` → 12 old / 4 new), each alert carrying its own `name` and
+  `revision`; then the rollout converged (`count(count by (revision) (…))` → **1**) and the alert
+  **cleared**. Firing and self-clearing are both confirmed on real data, which is the completion
+  notification's whole mechanism.
+- **The routing works.** `amtool config routes` shows
+  `{notification="deploy"} → receiver: email-deploy` under the default route, and
+  `amtool config routes test notification=deploy` returns `email-deploy`.
+- **The inhibition was real.** `InfoInhibitor` went active `2026-09-30T04:58:48Z` — the same moment
+  the alert began firing — and `amtool alert query` showed **no** `FluxRolloutInProgress` in
+  Alertmanager, active or `--inhibited`. `alertmanager_notifications_failed_total{integration=email}`
+  is 0 for every reason, so nothing failed to send; it was never dispatched.
+- promtool: **SUCCESS**, 53 rules, 6 scenarios, promtool 3.14.0 in the pinned toolbox.
+
+## What I did NOT verify
+
+- **No deploy mail has been observed in the inbox — this fix is UNVERIFIED end to end.** The
+  suppression was proven (nothing in Alertmanager, zero send failures) and the routing was proven
+  (`amtool config routes test` → `email-deploy`), but the delivered message is not. It can only be
+  proven by merging this and watching the next commit produce `[FLUX] applying` and then
+  `[FLUX] applied`. Same structural gap as PR #25, one layer further along.
+- **Whether the single email during the window was ours.**
+  `alertmanager_notifications_total{integration="email"}` went 226 → 227 while other alerts
+  (`Watchdog`, `CNPGPrimariesCoLocated`) were also active, and that counter carries no receiver
+  label, so the increment cannot be attributed. I am NOT claiming our mail was or was not sent — the
+  attribution is genuinely unavailable from this metric.
+- **Whether `InfoInhibitor` interacts with `FluxRolloutStuck`.** Stuck is `severity: warning`;
+  inhibit_rule 1 (`critical` → `warning|info`) requires an equal `alertname`, so it should not
+  apply — reasoned, not measured. Worth confirming the first time a rollout genuinely hangs.
+- **The `[FLUX] applying|applied` subject template** is still untested; `.Status` is assumed to be
+  `firing`/`resolved` in the notification template data.
+- **`required_approvals` disagreement, unresolved and not mine to settle.** Live branch protection
+  reads `required_approvals: 1`, while the `ci/gate.sh` comment introduced by PR #17 describes the
+  model as `required_approvals: 0` ("the gate is the approver"). `ci/gitea-settings.sh` may report
+  this as drift against `infra/gitea/expected-branch-protection.json`. Flagged only.
+- **The drift loop is still unexplained.** Five Kustomizations re-applying the same object every
+  10 minutes (event counts ~2500) — untouched, cause unknown, still deserves its own branch.

decisions/2026-09-30-node-health-render-device.md

@@ -0,0 +1,283 @@
+---
+date: 2026-09-30
+branch: feat/node-health-render-device
+title: The Intel render device is now self-re-measuring, not a fact someone checked once
+---
+
+## What changed
+
+### Why this probe has value at all
+
+**Nothing else in the platform would notice the device going missing.** Plex exposes no
+ServiceMonitor, so no alert fires on a silent fall back to software transcoding. And the
+manifest side mounts the device with `hostPath type: DirectoryOrCreate`, which means a node
+*without* the device mounts an **empty directory** — Plex starts, runs, and degrades quietly
+rather than failing loudly. There is no crash loop, no failed mount, no alert: just a hot CPU.
+This check is the only thing in the system that would surface it, which is the actual
+justification for the role carrying it.
+
+### The change
+
+`roles/node_health` grew a graphics / render-device probe. Nothing was installed, no module
+was loaded, no group was changed, nothing was rebooted: the prod nodes already have a working
+Intel render device (measured by hand on all three on 2026-09-30) and the point of this change
+is that the measurement now **re-runs forever** instead of decaying silently in a handoff note.
+
+The failure this exists to catch is silent by construction. Plex hardware-transcodes through
+`/dev/dri/renderD128`; if that node stops existing — node rebuild, a BIOS change that disables
+the onboard IGD, a kernel that binds a different DRM driver, a driver regression — Plex falls
+back to software transcoding on its own and the only symptom is a hot CPU.
+
+Four files:
+
+- `files/node_health_collect.py` — new `collect_graphics()`, wired into the **unprivileged**
+  pass (`main()`). Everything it reads is world-readable: `lstat()` on `/dev/dri/*`,
+  `grp.getgrgid()` for the owning group name, the `/sys/class/drm/card*/device/driver` symlink
+  target for the bound driver, `/sys/bus/pci/devices/*/class` for display-class (PCI base class
+  `0x03`) devices whether or not a driver is bound, `/sys/class/drm/card*/engine/*` for the
+  `vcs*`/`vecs*` media engines, `/proc/modules`, `/proc/cmdline`, and
+  `/sys/module/{i915,xe}/parameters/enable_guc`. `lspci` and `vainfo` were added to the
+  existing tool probe; both are optional and neither is depended on.
+- `tasks/assess.yml` — one shared derive task plus three checks: `graphics.render_device`
+  (PASS/FAIL/SKIP), `graphics.drm_driver` (PASS/WARN/FAIL/SKIP), `graphics.media_stack`
+  (INFO/SKIP).
+- `defaults/main.yml` — `node_health_graphics_expected_driver: i915`, so the one comparison the
+  check makes is data rather than task logic.
+- `templates/summary.txt.j2` — a `GRAPHICS / RENDER DEVICE` section, and
+  `roles/node_health/README.md` gained a section explaining the design and two new "known
+  limits".
+
+Three design rulings worth stating, because each is the kind of thing a later edit would get
+wrong:
+
+1. **The render node's GID is reported, never asserted.** It read `root:render`, gid **992**,
+   mode `0660` on all three prod nodes. The check does *not* compare against `992`. `render` is
+   a **systemd dynamic** allocation (`systemd-sysusers`), not a Debian static gid from
+   `base-passwd`, so a rebuild can legitimately move it — and Plex's container entrypoint stats
+   the device and joins whichever group owns it, so drift genuinely is not a fault. The
+   observed group name and number appear in the detail line, which makes drift *visible*
+   without making it an error. A hard `!= 992` would be a false alarm waiting for a reinstall.
+2. **The PCI scan is deliberately separate from the DRM scan.** `/sys/class/drm/card*` exists
+   only once a driver has *bound*, so a GPU with nothing attached has no `card0` and would
+   otherwise be indistinguishable from a machine with no GPU. Scanning the PCI bus separately
+   is what lets "no display device at all" be an honest **SKIP** (a VM guest — the same
+   convention `thermal.max` already uses for "no sensor on this hardware") while "a GPU is on
+   the bus and there is still no render node" is a **FAIL**.
+3. **GuC/HuC and host VAAPI userspace are INFO and must stay INFO.** GuC/HuC off
+   (`i915.enable_guc=0`) is an accepted state here and costs low-power H.264 encode *quality*
+   only. No host `vainfo` is not a defect at all — Plex ships its own libva and media driver
+   inside its container. Grading either would put a permanent WARN on a chosen configuration,
+   or invite someone to `apt install vainfo` on a node to clear a health check, and this role
+   installs nothing.
+
+`xe` bound instead of `i915` is a **WARN**, not a FAIL: the device still works, but the two
+drivers do not share a userspace media stack. On these nodes `xe.ko.xz` exists on disk and is
+bound to nothing.
+
+## What I verified
+
+### The real prod run (read-only, all three nodes)
+
+`--list-hosts` first, every time. It named exactly three hosts and nothing else:
+
+    play #1 (k3s_prod): Inspect node hardware health (read-only)
+        pattern: ['k3s_prod']
+        hosts (3): k3s-prod-3  k3s-prod-2  k3s-prod-1
+
+Then `--syntax-check` (rc 0), then the run:
+
+    ansible-playbook playbooks/node-health.yml -e node_health_hosts=k3s_prod --limit k3s_prod
+
+    k3s-prod-1 : ok=51  changed=3  unreachable=0  failed=0  skipped=1
+    k3s-prod-2 : ok=51  changed=2  unreachable=0  failed=0  skipped=1
+    k3s-prod-3 : ok=51  changed=2  unreachable=0  failed=0  skipped=1
+    PLAY rc=0
+
+(The `changed=` counts are the *controller-side* artifact writes under
+`infra/ansible/_artifacts/node-health/`, delegated to localhost. Nothing on any node changed —
+the collector task is `changed_when: false` and the role touches nothing.)
+
+All three nodes graded **PASS / PASS / INFO** on the new checks, 0 FAIL overall:
+
+    k3s-prod-1  VERDICT  0 FAIL · 1 WARN · 18 PASS · 2 SKIP · 6 INFO
+    k3s-prod-2  VERDICT  0 FAIL · 3 WARN · 15 PASS · 3 SKIP · 6 INFO
+    k3s-prod-3  VERDICT  0 FAIL · 2 WARN · 17 PASS · 2 SKIP · 6 INFO
+
+    [PASS] graphics.render_device — DRM render node present for hardware transcoding (/dev/dri/renderD*)
+    [PASS] graphics.drm_driver   — DRM driver bound to the display device (expected i915)
+    [INFO] graphics.media_stack  — Media engines, GuC/HuC firmware and host VAAPI userspace (informational)
+
+(The pre-existing WARNs and SKIPs are other checks — SMART, memattr, resolvers — and are not
+mine; none of them moved.)
+
+The new report section, **byte-identical on all three nodes**:
+
+    --------------------------------------------------------------------------------
+     GRAPHICS / RENDER DEVICE (the Plex hardware-transcoding path)
+    --------------------------------------------------------------------------------
+     pci  0000:00:02.0 00:02.0 VGA compatible controller [0300]: Intel Corporation CoffeeLake-S GT2 [UHD Graphics 630] [8086:3e98] (rev 02)
+                  driver i915
+     drm  card0        driver i915     at 0000:00:02.0  engines bcs0 rcs0 vcs0 vecs0
+     dev  card0        character special  mode 0660  root:video gid 44
+     dev  renderD128   character special  mode 0660  root:render gid 992
+     GuC/HuC     NOT READ — /sys/module/i915/parameters/enable_guc is not
+                  readable without root (i915 module parameters are mode 0400)
+                 no i915/xe parameter on the kernel cmdline
+     modules     amdgpu=false, i915=true, nouveau=false, nvidia=false, radeon=false, xe=false (/proc/modules — corroboration only; the bound-driver symlink above decides)
+     vainfo      NOT installed on this host — not a defect: Plex ships its own libva/media driver inside its container
+
+That reproduces every item of the 2026-09-30 hand measurement independently: `renderD128`
+character special, `root:render`, **gid 992**, mode `0660`; `card0` `root:video` gid 44 mode
+`0660`; `i915` bound; `xe` **not** loaded and bound to nothing; `[8086:3e98] (rev 02)`
+CoffeeLake-S GT2 UHD Graphics 630 at `00:02.0`; `vcs0` and `vecs0` live; no host `vainfo`.
+
+**One measured correction to my own phase-1 assumption:** `lspci` **is** present on all three
+prod nodes (`/usr/bin/lspci` — Debian ships `pciutils` by default). I had written that it was
+absent. It is still *treated* as optional, because `pciutils` is genuinely not declared in
+`node_baseline_packages` and depending on an undeclared package would be wrong — but the
+comments and README that asserted it was missing were factually wrong and are now corrected.
+Its presence is why the `pci` line above carries a readable device name rather than bare IDs.
+
+### The gate
+
+    DEV_KUBECONFIG=/dev/null ENGINE=<shim> ./infra/devcontainer/dev.sh run bash -c './ci/gate.sh'
+    GATE rc=3
+
+**rc 3 — UNDETERMINED. NOT green.** Nothing failed, and nothing is certified either. Exactly
+three stages did not run, all three the known local ceiling from a worktree, and **no fourth
+skip**:
+
+    [skip] spec-immutability  spec repo not present at /work/../home-network-k3s (set SPEC_REPO)
+    [skip] gitea-settings     SETTINGS_API_TOKEN is not set — cannot read the live Gitea rule
+    [skip] conformance        no cluster configured (CLUSTER_AVAILABLE!=true) — L2/L3 NOT RUN
+
+    [ ok ] decisions-log: pass      [ ok ] lint: pass       [ ok ] l0: pass
+    [ ok ] render-golden: pass      [ ok ] l1: pass         [ ok ] approval-policy: pass
+
+Both CLAUDE.md §3 worktree workarounds were needed and both worked: `DEV_KUBECONFIG=/dev/null`
+(the credential in the main checkout was **not** copied) and an `ENGINE` shim that bind-mounts
+the main checkout's `.git` read-only. No `tracked_files()` traceback appeared, which is how I
+know the shim took effect rather than the git stages silently degrading.
+
+`ansible-lint` was **not** run, because **`ci/` does not invoke it anywhere** — I grepped
+`ci/` and `.gitea/` and the lint stage is `yamllint -c ci/yamllint.yaml` only. I am not
+claiming to have matched a lint convention that does not exist.
+
+### The CI gate on the PR — a green tick that is exit 3, read from the log
+
+The required context `gate / gate (pull_request)` reported **`success`, "Successful in 1m40s"**
+on commit `a78f010`. That description matters: a *skipped* Gitea job reports `success` with
+"Has been skipped", so this one genuinely ran, and 1m40s matches CLAUDE.md §2's ~1m35s.
+
+**But the green tick does NOT mean `gate.sh` returned 0.** `.gitea/workflows/gate.yml:138` is
+`run: ./ci/gate.sh || [ "$?" -eq 3 ]` — the job tolerates rc 3 by design. So I fetched the job
+log (`/actions/runs/173/jobs/0/logs`; the `/api/v1/.../tasks/{id}/logs` endpoints 404 on this
+Gitea, the web route serves it) and read the gate's own headline:
+
+    [fail] MERGE GATE: UNDETERMINED — greenness was NOT ESTABLISHED.
+    [fail]   Stages that did not run: spec-immutability
+
+**So CI is also rc 3, with exactly ONE stage skipped — `spec-immutability`.** The green Gitea
+check is the tolerance swallowing that 3, not a rc 0.
+
+**CI verified two things my local run could not, and both came back green:**
+
+    [ ok ] stage gitea-settings: pass
+    [ ok ]   enable_push = false          enable_status_check = true
+    [ ok ]   required_approvals = 1       block_admin_merge_override = true
+    [ ok ]   block_on_rejected_reviews = true   dismiss_stale_approvals = true
+    [ ok ]   runners online: 1 (>= 1)
+    [ ok ] Gitea settings match the declaration.
+    [ ok ] stage approval-policy: pass
+    [ ok ] no architecturally/security-relevant paths touched — the GATE is the approver.
+
+My local run **skipped** `gitea-settings` (no `SETTINGS_API_TOKEN`) and could not give
+`approval-policy` a PR number. CI has the secret and `REQUIRE_GITEA_SETTINGS: "true"`, so a skip
+there would have failed the job. That is measured confirmation that the live Gitea matches
+`infra/gitea/expected-branch-protection.json`, and that `infra/ansible/**` needs no human
+reviewer. `lint` passed over 405 files. `conformance` SKIPPED in CI too
+(`CLUSTER_AVAILABLE != true`), so L2/L3 remains unverified there as well.
+
+Corroborated independently: `GET /repos/.../branches/main` →
+`protected=true user_can_push=false enable_status_check=true required_approvals=1`,
+contexts `["gate / gate (pull_request)"]`; `GET /admin/actions/runners` → `incluster-dind
+status=online`. And note the commit's **combined** state is `pending`, not success, because
+`gate / conformance (pull_request)` sits at "Blocked by required conditions" — that context is
+not in the required list, so it does not block, but the PR is not "all green" either.
+
+The gate's `lint` stage passed with one `line too long` **warning** on
+`roles/node_health/tasks/assess.yml:189` — that is pre-existing, in the SMART block, well
+above my insertion point, and warnings do not fail the stage.
+
+### Offline work (before the lock was released)
+
+- `python3 -m py_compile` on the collector: clean.
+- `collect_graphics()` executed for real against this workstation's hardware (an unrelated
+  machine, Raptor Lake-S UHD Graphics + an NVIDIA discrete GPU) and returned the whole
+  structure with no exception, correctly reporting two cards, two render nodes, the bound
+  driver per card, the `vcs0/vcs1/vecs0` media engines, and `enable_guc` as *not readable
+  without root* rather than as a fabricated `0`.
+- That last point is a real finding and changed the design: `/sys/module/i915/parameters/*` is
+  **mode 0400**, so an unprivileged pass cannot read `enable_guc`. It now reports
+  `NOT READ — <reason>` and `/proc/cmdline` is read as the world-readable second source. An
+  earlier draft would have silently reported a null.
+- Two other bugs found and fixed by running it rather than reasoning about it:
+  `/dev/dri/by-path` is a **directory** and was being `lstat()`ed as a device; and
+  `/sys/class/drm` carries one entry per *connector* (`card0-HDMI-A-1`), which had to be
+  excluded from the card scan.
+- All three checks and the new template section were rendered through a standalone Jinja
+  harness (Ansible is not on the host — CLAUDE.md §5) against **seven** fact sets: the real
+  workstation; GPU present with the render node removed; no display device at all; `xe` bound
+  in place of `i915`; a display device with **no** driver bound; `renderD128` present but not a
+  character device; and a shape with neither `lspci` nor `vainfo`. Zero template errors, and
+  the statuses came out as designed — `FAIL/PASS/INFO`, `SKIP/SKIP/SKIP`, `PASS/WARN/INFO`,
+  `FAIL/FAIL/INFO`, `FAIL/PASS/INFO` respectively. The harness supplies stand-ins for the
+  Ansible-only filters (`bool`, `dict2items`, `flatten`, `zip`, `regex_replace`) and matches
+  Ansible's `trim_blocks=True`.
+  **Read that for exactly what it is: evidence that the LOGIC is right, and no evidence
+  whatsoever that the HARDWARE DETECTION is.** Six of those seven fact sets were hand-mutated
+  dictionaries, not machines. They are not hardware tests and must not be written up as if
+  they were.
+
+## What I did NOT verify
+
+- **The FAIL path has never fired on a real node.** Every prod node has a working render
+  device, and this role is read-only, so a device cannot be taken away to prove the check
+  catches its absence. The failure branches were exercised against **synthetic fact sets
+  only** (see above). I am not claiming the failure path is tested against hardware.
+- **`xe` detection is likewise untested against reality.** No node here has `xe` bound — the
+  module exists on disk as `xe.ko.xz` and is bound to nothing — so the WARN branch was only
+  ever driven by a mutated fact set. If `xe` ever does bind, the *shape* of
+  `/sys/class/drm/card*` under it is something I have assumed matches i915's (same
+  `device/driver` symlink, same `engine/*` directories). That assumption is unverified.
+- **The media-engine sysfs path is confirmed on these nodes but not proven portable.**
+  `vcs0`/`vecs0` were read from `/sys/class/drm/card0/engine/*` on all three prod nodes, so it
+  is measured here. I did **not** confirm against kernel source that no other kernel version or
+  driver publishes engines elsewhere. If one does, the check reports "none exposed" — an INFO
+  line, not a false verdict, which is why this failure mode is tolerable.
+- **`enable_guc` is still unread on prod.** The report says `NOT READ — mode 0400`, which is
+  honest but means I have **not** confirmed by measurement that GuC/HuC is off on these nodes;
+  I only know the kernel cmdline carries no `i915.enable_guc=` override. The brief's ground
+  truth says `i915.enable_guc=0`; my check does not corroborate that value, it declines to
+  guess it. Reading it would need root, and it is INFO either way, so I left it alone.
+- **Not a transcode test.** These checks prove the render *device* exists, is a character
+  device, and which driver owns it. They do **not** prove a transcode succeeds — that needs a
+  VAAPI round trip inside Plex's own container with Plex's own libva, and is out of scope for a
+  node-level check that installs nothing.
+- **Greenness was never established, locally or in CI.** Both runs returned **rc 3**. My local
+  run skipped three stages (`spec-immutability`, `gitea-settings`, `conformance`); CI skipped
+  one (`spec-immutability`) and its own headline says `MERGE GATE: UNDETERMINED`. **I am not
+  describing this PR as green**, and the green Gitea tick must not be read as one: the workflow
+  line is `./ci/gate.sh || [ "$?" -eq 3 ]`, so it is a tolerated 3.
+- **L2/L3 conformance did not run anywhere** — `CLUSTER_AVAILABLE != true` in both. Whatever
+  runtime requirements this touches remain UNVERIFIED; only the L0/L1 offline subset passed.
+- **`spec-immutability` ran in neither.** The sibling spec repo is checked out in neither my
+  worktree nor the CI workspace, so nothing confirms this change does not drift from the spec.
+  It is the expected, tolerated skip — but it is still a skip, not a pass.
+- **No claim about the live platform beyond what was printed.** Per CLAUDE.md §2b this repo is
+  not evidence about prod; the only prod facts I assert are the ones quoted verbatim above.
+  Branch protection and runner state I did query directly, and the CI `gitea-settings` stage
+  passed — so those two I assert on measurement, not on this file's prose.
+- **The stale dev inventory was left alone deliberately.** `hosts.ini` still defines the
+  `k3s-dev-*` groups as the default target of most playbooks and the dev cluster no longer
+  exists. That is real, it is out of this change's scope, and it is unclaimed work.

infra/ansible/roles/node_health/README.md

@@ -19,9 +19,9 @@ Serves **R-ENV-01** (you cannot certify a node you have not measured), **R-ENV-0
 
 ## Contract
 
-- **Read-only and side-effect-free.** It reads `/sys`, `/proc`, `/etc`, runs `lsblk`/`lscpu`,
-  and — only when it can escalate — `smartctl`. It writes nothing to the node and
-  **installs nothing**. `smartmontools` is declared in `node_baseline_packages`; if it is
+- **Read-only and side-effect-free.** It reads `/sys`, `/proc`, `/etc`, runs `lsblk`/`lscpu`
+  (and `lspci` only if it happens to be installed), and — only when it can escalate —
+  `smartctl`. It writes nothing to the node and **installs nothing**. `smartmontools` is declared in `node_baseline_packages`; if it is
   absent the SMART checks SKIP with that as the stated reason (operator ruling 2026-08-31:
   package installation is `node_baseline`'s job, never a health check's, never a manual
   `apt-get`).
@@ -50,6 +50,9 @@ Serves **R-ENV-01** (you cannot certify a node you have not measured), **R-ENV-0
 | `memory.available`, `memory.swap`, `memory.ecc` | headroom, kubelet's swap-off prerequisite **and whether it survives a reboot** (see [Swap off is not the same as swap disabled](#swap-off-is-not-the-same-as-swap-disabled)), EDAC correctable/uncorrectable counters |
 | `memory.physical_total` | **is this machine using the RAM it has?** `/proc/zoneinfo` present-vs-managed pages (no root, metal or VM) and `MemTotal` vs the DIMM capacity SMBIOS reports (`dmidecode -t 17`, root, bare metal). Cause-independent by design — see [The EFI memattr check](#the-efi-memattr-check) |
 | `cpu.throttle`, `cpu.inventory`, `cpu.virtualisation` | thermal throttle events since boot, topology + frequency scaling, VT-x/AMD-V + `/dev/kvm` (KubeVirt, R-PLAT-03) |
+| `graphics.render_device` | is there a usable `/dev/dri/renderD*` character device — the path Plex hardware-transcodes through. See [The render-device check](#the-render-device-check) |
+| `graphics.drm_driver` | which DRM driver is bound to the display device, against `node_health_graphics_expected_driver` (`i915` here) |
+| `graphics.media_stack` | **INFO only**: `vcs*`/`vecs*` media engines, GuC/HuC firmware state, host VAAPI userspace. None of these is ever graded — see below for why |
 | `thermal.max` | hottest sensor across thermal zones and hwmon chips |
 | `pressure.cpu` / `.memory` / `.io` | PSI `some avg60` — dev learned to care about CPU PSI specifically |
 | `network.link`, `network.errors`, `network.resolvers` | link state/speed, NIC error counters, DNS upstream redundancy per address family |
@@ -91,6 +94,78 @@ used to blame that state on "this node has not been baselined yet", which sent t
 back to re-run the role that had already run.
 
 
+## The render-device check
+
+Plex transcodes on the iGPU through `/dev/dri/renderD128`. **When that node stops existing,
+nothing fails loudly.** Plex falls back to software transcoding by itself; the only symptom
+is a hot CPU and stuttering clients. A node rebuild, a BIOS change that disables the onboard
+IGD, a kernel that binds a different DRM driver, or a driver regression all produce exactly
+that silent degradation.
+
+The state was measured by hand on all three prod nodes on 2026-09-30 and found working. **A
+fact measured once decays silently**, so it is re-measured on every health run instead of
+living in a runbook. Nothing is installed, no module is loaded, no group is changed — the
+role's read-only contract is unchanged.
+
+| fact | where it comes from | root? |
+|---|---|---|
+| `/dev/dri` contents, ownership, mode, char-vs-not | `lstat()` on each entry | no |
+| owning group **name** for the render node's gid | `grp.getgrgid()` | no |
+| bound DRM driver | `/sys/class/drm/card*/device/driver` symlink target | no |
+| is the iGPU on the bus at all | `/sys/bus/pci/devices/*/class` (PCI base class `0x03`) | no |
+| media engines (`vcs*`, `vecs*`) | `/sys/class/drm/card*/engine/*` | no |
+| module load state | `/proc/modules` | no |
+| GuC/HuC | `/sys/module/i915/parameters/enable_guc` + `/proc/cmdline` | **parameter file is mode 0400** |
+
+### The PCI scan is separate from the DRM scan on purpose
+
+`/sys/class/drm/card*` exists only once a driver has **bound**. A machine whose iGPU sits on
+the bus with nothing attached has no `card0` at all — and that is precisely the failure being
+hunted. So the display device is looked for on the PCI bus independently, from sysfs, which
+is always there. That is what lets `graphics.render_device` distinguish
+
+- *no GPU in this machine* → **SKIP** (a VM guest; nothing to grade, the same convention
+  `thermal.max` uses for "no sensor on this hardware"), from
+- *a GPU is on the bus and there is still no render node* → **FAIL**.
+
+`lspci` is used **only** to decorate the PCI entry with a readable name, and it is treated as
+optional because it is: `pciutils` is **not** declared in `node_baseline_packages`, so nothing
+in this repo guarantees it. It did turn out to be present on all three prod nodes
+(`/usr/bin/lspci`, measured 2026-09-30 — Debian installs `pciutils` by default), but depending
+on that would mean depending on an undeclared package. Absent, `description` is `null`, the
+numeric IDs are printed instead, and no verdict changes.
+
+### The render node's GID is reported, never asserted
+
+The render device was `root:render`, **gid 992**, mode `0660` on all three prod nodes on
+2026-09-30. The check does **not** compare against `992`, and must not be changed to.
+`render` is a **systemd dynamic allocation** (`systemd-sysusers`), not a Debian static gid
+from `base-passwd`, so a rebuilt node can legitimately land on a different number. Plex's own
+container entrypoint stats the device and joins whichever group owns it, so drift genuinely
+is not a fault. Recording the observed group name and gid in the detail line makes drift
+**visible** without making it an error — a hard `!= 992` would be a false alarm waiting for a
+reinstall.
+
+What *is* configurable is the expected DRM driver, `node_health_graphics_expected_driver`
+(default `i915`), so the verdict stays out of task logic. `xe` bound instead of `i915` is a
+**WARN**, not a FAIL: the device still works, but the two drivers do not share a userspace
+media stack and a libva/iHD build that transcodes correctly against one is not automatically
+right for the other. On these nodes `xe.ko.xz` exists on disk and is bound to nothing.
+
+### Two things that are informational and must stay that way
+
+- **GuC/HuC firmware not loaded** (`i915.enable_guc=0`) is a known, accepted state here. It
+  costs low-power H.264 encode *quality* only; decode and encode both still run on the media
+  engines. Grading it would put a permanent WARN on a chosen configuration.
+- **No host VAAPI userspace / no `vainfo`** is **not a defect**. Plex ships its own libva and
+  media driver inside its container, so the host needs neither. Flagging it would invite
+  someone to `apt install vainfo` on a node to clear a health check — and this role installs
+  nothing.
+
+`enable_guc` is one of i915's `0400` module parameters, so an unprivileged pass usually
+cannot read it. It reports as an honest `NOT READ — <reason>` rather than a fabricated `0`,
+with `/proc/cmdline` as the world-readable second source for an explicit boot override.
+
 ## The EFI memattr check
 
 `infra/PROD-PROVISIONING.md` §0b is authoritative; this is only what the check needs.
@@ -273,3 +348,10 @@ stays `null` — no claim is made either way.
   but the wear/endurance context SKIPs rather than guessing.
 - `ioerr_cnt` counts commands the kernel saw fail, which includes benign rejected or
   unsupported commands during discovery. Attribution needs `dmesg`, which needs root.
+- `graphics.render_device`'s **FAIL path has never fired against a real node** — every prod
+  node has a working render device, and the role is read-only so one cannot be taken away to
+  prove it. The failure branches were exercised against synthetic fact sets only. The same
+  applies to the `xe`-bound WARN: no node here has `xe` bound.
+- `graphics.*` proves the render **device** exists and which driver owns it. It does **not**
+  prove a transcode succeeds — that needs a VAAPI round trip inside Plex's own container,
+  with Plex's own libva, which is out of scope for a node-level check that installs nothing.

infra/ansible/roles/node_health/defaults/main.yml

@@ -35,6 +35,24 @@ node_health_try_privileged: true
 # --nocheck=standby: never spin up a sleeping disk just to read it. Read-only hygiene.
 node_health_smartctl_args: "--json=c --all --nocheck=standby"
 
+# --- Graphics / render device ---------------------------------------------------------
+# The DRM driver this site EXPECTS to be bound to its display device. Measured on all three
+# prod nodes 2026-09-30: `i915` on the CoffeeLake-S GT2 [UHD Graphics 630] iGPU of every HP
+# EliteDesk 800 G5 Mini. The newer `xe` module is present on disk as xe.ko.xz but is bound to
+# nothing, and that difference matters enough to surface: the two drivers do not share a
+# userspace media stack (a libva/iHD build that works against i915 is not automatically the
+# right one for xe), so a silent switch would change Plex's transcoding path. A site on AMD
+# or NVIDIA sets this to `amdgpu` / `nouveau` / `nvidia` rather than editing task logic.
+#
+# WHAT IS DELIBERATELY *NOT* A SETTING HERE: the numeric GID of the render node's owning
+# group. `render` is a systemd DYNAMIC allocation (systemd-sysusers), not a Debian static
+# one, so a rebuilt node may legitimately land on a different number — it was 992 on all
+# three prod nodes on 2026-09-30, and an assertion against that literal would be a false
+# alarm waiting to happen. Plex's own container entrypoint stats the device and joins
+# whichever group owns it, so drift genuinely is not a fault. The observed group name and GID
+# are therefore REPORTED in the check detail and never graded.
+node_health_graphics_expected_driver: i915
+
 # --- Thresholds ---------------------------------------------------------------------
 # All verdicts come from here, so a site can retune without touching task logic.
 node_health_thresholds:

infra/ansible/roles/node_health/files/node_health_collect.py

@@ -35,10 +35,13 @@
 # =============================================================================
 
 import glob
+import grp
 import json
 import os
+import pwd
 import re
 import shutil
+import stat
 import subprocess
 import sys
 import time
@@ -756,6 +759,212 @@ def collect_pressure():
     return out
 
 
+# --- Graphics / DRM render device -----------------------------------------------------
+# WHY THIS IS HERE AT ALL. Plex transcodes on the iGPU through /dev/dri/renderD128. If that
+# node stops existing — a node rebuild, a BIOS change that disables the IGD, a kernel that
+# binds a different DRM driver — nothing breaks loudly: Plex silently falls back to software
+# transcoding and the only symptom is a hot CPU. So the render device is measured on every
+# health run rather than being a fact someone established once by hand.
+#
+# EVERYTHING BELOW IS UNPRIVILEGED. /dev/dri is world-traversable, the device nodes are
+# stat()able by anyone, /sys/class/drm and /sys/bus/pci/devices are world-readable, and so
+# are the module parameters under /sys/module. Nothing here needs root, so nothing here
+# belongs in the privileged pass. (GuC/HuC *load* status lives in debugfs, which does need
+# root AND debugfs mounted; the module PARAMETER below is the unprivileged stand-in and is
+# what actually decides whether the firmware is loaded at all.)
+#
+# THE PCI SCAN IS DELIBERATELY SEPARATE FROM THE DRM SCAN. /sys/class/drm/card* only exists
+# once a driver has BOUND. A machine whose iGPU is on the bus with no driver bound has no
+# card0 at all, and that is precisely the failure this is meant to catch — so the display
+# device is looked for on the PCI bus independently, from sysfs, which is always there.
+# `lspci` is used ONLY to decorate that with a human-readable name, and it is treated as
+# optional because it IS optional: pciutils is not declared in node_baseline_packages, so
+# nothing in this repo guarantees it. It did turn out to be present on all three prod nodes
+# (/usr/bin/lspci, measured 2026-09-30 — Debian installs pciutils by default), but relying on
+# that would make the collector depend on an undeclared package. A missing lspci leaves
+# `description` null, the numeric IDs are reported instead, and no verdict changes.
+DISPLAY_PCI_CLASS_PREFIX = "0x03"  # PCI base class 03 = display controller (VGA/3D/other)
+# DRM drivers worth reporting the load state of. The bound-driver symlink is authoritative
+# (a built-in driver never appears in /proc/modules); this is corroboration only, and it is
+# how "xe.ko.xz exists on disk but is bound to nothing" becomes a visible fact.
+DRM_MODULES = ("i915", "xe", "amdgpu", "radeon", "nouveau", "nvidia")
+
+
+def _uid_name(uid):
+    try:
+        return pwd.getpwuid(uid).pw_name
+    except (KeyError, OverflowError, TypeError, OSError):
+        return None
+
+
+def _gid_name(gid):
+    """Group NAME for a numeric gid, or None when nothing resolves it.
+
+    Reported as an OBSERVED value, never asserted against a literal. The `render` group is
+    a systemd DYNAMIC allocation (it is created by systemd-sysusers, not fixed by Debian's
+    static base-passwd list), so its gid can legitimately differ after a rebuild. Plex's own
+    container init stats the device and joins whatever group owns it, so a moved gid is
+    drift to notice, not a fault to fail on."""
+    try:
+        return grp.getgrgid(gid).gr_name
+    except (KeyError, OverflowError, TypeError, OSError):
+        return None
+
+
+def _module_param(mod, param):
+    """One /sys/module/<mod>/parameters/<param>, with WHY it is missing when it is.
+
+    Three outcomes that must not be conflated: a real value; "the module exposes no such
+    parameter" (not loaded, built in, or a driver that simply has no such knob — xe has no
+    enable_guc, GuC is mandatory there); and "the file exists but is mode 0400". Most i915
+    module parameters are `i915_param_named(..., 0400, ...)` — root-only — so an
+    unprivileged pass legitimately cannot read them. Returning null with the reason keeps
+    that an honest UNKNOWN instead of a fabricated 0. read_text() also records the
+    permission denial in UNREADABLE, so the summary lists it with everything else root
+    would add."""
+    path = "/sys/module/%s/parameters/%s" % (mod, param)
+    if not os.path.exists(path):
+        return {"value": None, "reason": "%s exposes no %s parameter (module not loaded, "
+                                         "built in, or no such knob on this driver)" % (mod, param)}
+    value = read_text(path)
+    if value is None:
+        return {"value": None, "reason": "%s is not readable without root (i915 module "
+                                         "parameters are mode 0400)" % path}
+    return {"value": value, "reason": None}
+
+
+def _dev_node(path):
+    """stat() one /dev/dri entry. lstat, so a symlink is reported as the symlink it is."""
+    try:
+        st = os.lstat(path)
+    except OSError as exc:
+        UNREADABLE.append({"path": path, "reason": "stat failed: %s" % exc})
+        return None
+    return {
+        "path": path,
+        "name": os.path.basename(path),
+        "char_device": stat.S_ISCHR(st.st_mode),
+        "mode": "%04o" % stat.S_IMODE(st.st_mode),
+        "uid": st.st_uid,
+        "gid": st.st_gid,
+        "owner": _uid_name(st.st_uid),
+        "group": _gid_name(st.st_gid),
+    }
+
+
+def collect_graphics():
+    dri_dir = "/dev/dri"
+    dri_present = os.path.isdir(dri_dir)
+    devices = []
+    if dri_present:
+        for path in sorted(glob.glob(dri_dir + "/*")):
+            # /dev/dri/by-path/ is a directory of symlinks, not a device. Skipping
+            # directories rather than filtering to char devices is deliberate: anything
+            # in here that is NOT a character special file is an anomaly worth seeing, and
+            # `char_device: false` is how it becomes visible.
+            if os.path.isdir(path):
+                continue
+            entry = _dev_node(path)
+            if entry is not None:
+                devices.append(entry)
+    render_nodes = [d for d in devices if d["name"].startswith("renderD")]
+
+    # Bound DRM devices. /sys/class/drm also holds one entry per CONNECTOR
+    # (card0-HDMI-A-1, card0-DP-1 ...) — those are outputs, not devices, and are skipped.
+    cards = []
+    for cdir in sorted(glob.glob("/sys/class/drm/card[0-9]*")):
+        name = os.path.basename(cdir)
+        if "-" in name:
+            continue
+        driver = None
+        drvlink = cdir + "/device/driver"
+        if os.path.islink(drvlink):
+            driver = os.path.basename(os.path.realpath(drvlink))
+        address = None
+        devlink = cdir + "/device"
+        if os.path.islink(devlink):
+            address = os.path.basename(os.path.realpath(devlink))
+        # i915/xe publish one directory per hardware engine. vcs* is a video (H.264/HEVC)
+        # engine and vecs* the video-enhancement engine: those two are what a transcode
+        # actually runs on, so their presence is the difference between "a GPU is bound"
+        # and "this GPU can do media work".
+        engines = sorted(
+            {
+                os.path.basename(p)
+                for p in (glob.glob(cdir + "/engine/*") + glob.glob(cdir + "/device/engine/*"))
+                if os.path.isdir(p)
+            }
+        )
+        cards.append(
+            {
+                "card": name,
+                "driver": driver,
+                "pci_address": address,
+                "vendor_id": read_text(cdir + "/device/vendor"),
+                "device_id": read_text(cdir + "/device/device"),
+                "engines": engines,
+                "media_engines": [e for e in engines if e.startswith(("vcs", "vecs"))],
+            }
+        )
+
+    # Display-class devices on the PCI bus, driver bound or not.
+    pci_display = []
+    for pdir in sorted(glob.glob("/sys/bus/pci/devices/*")):
+        class_id = read_text(pdir + "/class") or ""
+        if not class_id.startswith(DISPLAY_PCI_CLASS_PREFIX):
+            continue
+        address = os.path.basename(pdir)
+        driver = None
+        if os.path.islink(pdir + "/driver"):
+            driver = os.path.basename(os.path.realpath(pdir + "/driver"))
+        description = None
+        rc, out, _ = run(["lspci", "-nn", "-s", address])
+        if rc == 0 and out.strip():
+            description = out.strip().splitlines()[0]
+        pci_display.append(
+            {
+                "address": address,
+                "class_id": class_id or None,
+                "vendor_id": read_text(pdir + "/vendor"),
+                "device_id": read_text(pdir + "/device"),
+                "revision": read_text(pdir + "/revision"),
+                "driver": driver,
+                "description": description,
+            }
+        )
+
+    loaded = set()
+    for line in (read_text("/proc/modules") or "").splitlines():
+        fields = line.split()
+        if fields:
+            loaded.add(fields[0])
+    modules = {m: (m in loaded) for m in DRM_MODULES}
+
+    # GuC/HuC. i915's `enable_guc` is a bitmask: 0 = neither, 1 = GuC submission, 2 = HuC
+    # firmware, 3 = both, -1 = whatever the driver defaults to on this platform. It is the
+    # one place the state is visible without root AND without debugfs — but the sysfs file
+    # is mode 0400, so unprivileged it usually reads back as an honest UNKNOWN. The kernel
+    # command line is the world-readable second source: an explicit `i915.enable_guc=` there
+    # is authoritative about what was ASKED for, even when the parameter file cannot be read.
+    uc = {mod: {"enable_guc": _module_param(mod, "enable_guc")} for mod in ("i915", "xe")}
+    cmdline_params = [
+        token
+        for token in (read_text("/proc/cmdline") or "").split()
+        if token.startswith(tuple("%s." % m for m in DRM_MODULES))
+    ]
+
+    return {
+        "dri_present": dri_present,
+        "devices": devices,
+        "render_nodes": render_nodes,
+        "drm_cards": cards,
+        "pci_display": pci_display,
+        "modules": modules,
+        "uc": uc,
+        "cmdline_params": cmdline_params,
+    }
+
+
 # --- Storage ------------------------------------------------------------------------
 PSEUDO_FS = {
     "proc", "sysfs", "devtmpfs", "devpts", "tmpfs", "cgroup", "cgroup2", "pstore",
@@ -1095,7 +1304,15 @@ def collect_os():
 # we only DETECT, and the role skips the SMART checks with an accurate reason.
 def collect_tools():
     tools = {}
-    for tool in ("smartctl", "nvme", "ethtool", "dmidecode", "lsblk", "lscpu"):
+    # lspci (pciutils) and vainfo (libva-utils) are BOTH optional and NEITHER is declared in
+    # node_baseline_packages, so nothing in this repo guarantees either. Measured on prod
+    # 2026-09-30: lspci IS there (/usr/bin/lspci — Debian ships pciutils by default) and
+    # vainfo is NOT. lspci only decorates the PCI display entry with a readable name; vainfo
+    # is not needed on the host at all, because Plex ships its own libva and media driver
+    # inside its container. They are probed so the report can state their presence or absence
+    # as a fact instead of leaving the reader to wonder — and so nothing here is ever tempted
+    # to install them. This role installs nothing.
+    for tool in ("smartctl", "nvme", "ethtool", "dmidecode", "lsblk", "lscpu", "lspci", "vainfo"):
         tools[tool] = which(tool)
     return tools
 
@@ -1127,6 +1344,7 @@ def main():
         "os": collect_os(),
         "dmi": collect_dmi(),
         "cpu": collect_cpu(),
+        "graphics": collect_graphics(),
         "memory": collect_memory(),
         "thermal": collect_thermal(),
         "pressure": collect_pressure(),

infra/ansible/roles/node_health/tasks/assess.yml

@@ -652,6 +652,204 @@
          ~ (', lscpu Virtualization=' ~ c.virtualization if c.virtualization else '')
          ~ (', running as a guest of ' ~ c.hypervisor_vendor if c.is_virtual_guest | bool else '') }}
 
+# --- Graphics / render device ----------------------------------------------------------
+# WHY A HEALTH CHECK AND NOT A NOTE IN A RUNBOOK. Plex transcodes on the iGPU through
+# /dev/dri/renderD128. When that node stops existing nothing fails loudly — Plex falls back
+# to software transcoding on its own and the only symptom is a hot CPU and stuttering
+# clients. A node rebuild, a BIOS setting that disables the onboard IGD, or a kernel that
+# binds a different DRM driver all produce exactly that silent degradation. It was measured
+# by hand on all three prod nodes on 2026-09-30 and found working; a fact measured once
+# decays silently, so it is re-measured on every health run instead.
+#
+# READ-ONLY, AND UNPRIVILEGED. Every fact behind these three checks comes from the
+# unprivileged pass: stat() on /dev/dri, the /sys/class/drm bound-driver symlink,
+# /sys/bus/pci/devices class codes, /proc/modules and /proc/cmdline. The role installs
+# nothing (no vainfo, no pciutils), loads no module and changes no group — see the role
+# README. The ONE fact that is root-gated is i915's enable_guc module parameter (mode 0400),
+# and it reports as an honest UNKNOWN with the reason rather than as a 0.
+#
+# THE THREE VERDICTS ARE SPLIT ON PURPOSE:
+#   graphics.render_device  the OUTCOME — can anything hardware-transcode on this node.
+#   graphics.drm_driver     the CAUSE side — what is bound, and is it what this site expects.
+#   graphics.media_stack    INFO only. GuC/HuC and host VAAPI userspace both belong here and
+#                           NEITHER is ever a failure; see the task's own comment for why.
+- name: Assess — locate the display device and its bound driver (once, shared by three checks)
+  ansible.builtin.set_fact:
+    node_health_render:
+      # Display-class PCI devices (base class 0x03), driver bound or not. This is the
+      # question "is there a GPU in this machine at all", and it is answered from the PCI
+      # bus rather than from /sys/class/drm because a card* entry only exists once a driver
+      # has BOUND — so a GPU with nothing bound to it has no card* and would otherwise look
+      # identical to a machine with no GPU.
+      display_devices: "{{ g.pci_display }}"
+      bound_drivers: >-
+        {{ g.pci_display | map(attribute='driver') | select('string') | unique | list }}
+      # Only a CHARACTER SPECIAL file is a usable render node. Anything else called renderD*
+      # is an anomaly, not a device, and must not be counted as one.
+      render_chardevs: "{{ g.render_nodes | selectattr('char_device') | list }}"
+      # Video (vcs*) and video-enhancement (vecs*) engines across every bound card — the
+      # difference between "a GPU is bound" and "this GPU can do media work".
+      media_engines: >-
+        {{ g.drm_cards | map(attribute='media_engines') | flatten | unique | sort | list }}
+  vars:
+    ansible_become: false
+    g: "{{ node_health_facts.graphics }}"
+
+- name: Assess — DRM render node for hardware transcoding
+  ansible.builtin.set_fact:
+    node_health_checks: "{{ node_health_checks + [{
+      'id': 'graphics.render_device',
+      'title': 'DRM render node present for hardware transcoding (/dev/dri/renderD*)',
+      'status': render_status,
+      'detail': render_detail }] }}"
+  vars:
+    ansible_become: false
+    g: "{{ node_health_facts.graphics }}"
+    r: "{{ node_health_render }}"
+    # SKIP, not PASS and not FAIL, when the machine has no display device at all: there is
+    # then nothing to grade, and the same convention thermal.max already uses for "no sensor
+    # on this hardware" applies. FAIL is reserved for the state that actually breaks Plex —
+    # a GPU IS on the bus and there is still no render node.
+    render_status: >-
+      {{ 'SKIP' if (r.display_devices | length) == 0
+         else ('PASS' if (r.render_chardevs | length) > 0 else 'FAIL') }}
+    dri_listing: >-
+      {{ (g.devices | map(attribute='name') | join(', ')) if (g.devices | length) > 0
+         else 'nothing' }}
+    render_detail: >-
+      {%- if (r.display_devices | length) == 0 -%}
+      this machine exposes no display-class PCI device (base class 0x03) at all, so there is
+      no GPU here for a render node to belong to and hardware transcoding is not available on
+      this node by construction. Normal for a VM guest. Measured from /sys/bus/pci/devices,
+      not assumed.
+      {%- elif (r.render_chardevs | length) > 0 -%}
+      {{ r.render_chardevs | length }} render node(s):
+      {% for d in r.render_chardevs %}{{ d.path }} (character special, mode {{ d.mode }},
+      owner {{ d.owner | default(d.uid, true) }}, group {{ d.group | default('unresolved', true) }}
+      gid {{ d.gid }}){{ ', ' if not loop.last else '' }}{% endfor %}.
+      /dev/dri holds: {{ dri_listing }}.
+      THE OWNING GROUP AND GID ARE REPORTED AS OBSERVED, NEVER ASSERTED against a literal:
+      `render` is a systemd DYNAMIC allocation rather than a Debian static one, so a rebuilt
+      node may legitimately land on a different number (all three prod nodes read gid 992 on
+      2026-09-30), and Plex's container entrypoint stats the device and joins whichever group
+      owns it. Drift is therefore visible in this line without being a failure.
+      {%- else -%}
+      HARDWARE TRANSCODING IS BROKEN ON THIS NODE. A display-class device IS present on the
+      PCI bus ({{ r.display_devices | map(attribute='address') | join(', ') }}) but there is
+      no usable character-special render node: /dev/dri
+      {{ 'does not exist' if not (g.dri_present | bool) else 'holds ' ~ dri_listing }}.
+      {{ ('Note that /dev/dri holds ' ~ (g.render_nodes | map(attribute='name') | join(', '))
+      ~ ' — present, but NOT character special, which is an anomaly in its own right. ')
+         if (g.render_nodes | length) > 0 else '' }}
+      Nothing fails loudly in this state — Plex silently falls back to software transcoding
+      and the only symptom is CPU load. Check graphics.drm_driver below for whether a DRM
+      driver bound at all, then whether the onboard IGD is still enabled in BIOS.
+      {%- endif -%}
+
+- name: Assess — DRM driver bound to the display device
+  ansible.builtin.set_fact:
+    node_health_checks: "{{ node_health_checks + [{
+      'id': 'graphics.drm_driver',
+      'title': 'DRM driver bound to the display device (expected ' ~ expected ~ ')',
+      'status': driver_status,
+      'detail': driver_detail }] }}"
+  vars:
+    ansible_become: false
+    g: "{{ node_health_facts.graphics }}"
+    r: "{{ node_health_render }}"
+    expected: "{{ node_health_graphics_expected_driver }}"
+    # WARN rather than FAIL when a DIFFERENT driver is bound (the `xe` case): the device
+    # still works, but the userspace media stack is not the same one, so it is a change the
+    # operator must see before a transcode regression surfaces as a user complaint. FAIL is
+    # for nothing bound at all, which is the cause of a missing render node.
+    driver_status: >-
+      {{ 'SKIP' if (r.display_devices | length) == 0
+         else ('FAIL' if (r.bound_drivers | length) == 0
+               else ('PASS' if expected in r.bound_drivers else 'WARN')) }}
+    driver_detail: >-
+      {%- if (r.display_devices | length) == 0 -%}
+      no display-class PCI device on this machine, so no DRM driver can be bound to one.
+      Measured from /sys/bus/pci/devices.
+      {%- else -%}
+      {% for p in r.display_devices %}{{ p.address }}
+      {{ p.description | default(((p.vendor_id | default('?', true)) ~ ':' ~ (p.device_id | default('?', true))), true) }}
+      -> driver {{ p.driver | default('NONE BOUND', true) }}{{ '; ' if not loop.last else '' }}{% endfor %}.
+      {{ ('DRM cards: ' ~ (g.drm_cards | map(attribute='card') | zip(g.drm_cards | map(attribute='driver'))
+           | map('join', '=') | join(', ')) ~ '. ') if (g.drm_cards | length) > 0
+         else 'No /sys/class/drm/card* entry exists, which is consistent with no driver being bound. ' }}
+      Module load state (/proc/modules, corroboration only — a built-in driver never appears
+      there, the bound-driver symlink above is what decides):
+      {{ g.modules | dict2items | map(attribute='key') | zip(g.modules | dict2items | map(attribute='value') | map('string'))
+         | map('join', '=') | join(', ') }}.
+      {%- if (r.bound_drivers | length) == 0 %}
+      NOTHING IS BOUND to the display device. That is why there is no render node: the DRM
+      subsystem creates /dev/dri/renderD* only when a driver attaches. Check whether the
+      module exists for this kernel and whether it was blacklisted or failed to probe.
+      {%- elif expected in r.bound_drivers %}
+      This is the expected driver for this site (node_health_graphics_expected_driver).
+      {%- else %}
+      EXPECTED `{{ expected }}`, GOT `{{ r.bound_drivers | join(', ') }}`. The device still
+      works, so this is not an outage — but the two DRM drivers do not share a userspace
+      media stack, and a libva/iHD build that transcodes correctly against one is not
+      automatically right for the other. Confirm Plex still hardware-transcodes before
+      treating this as benign.
+      {%- endif %}
+      {%- endif -%}
+
+# INFO ONLY, AND THAT IS A DELIBERATE RULING, NOT AN OVERSIGHT:
+#
+#   GuC/HuC firmware not loaded (i915.enable_guc=0) — the accepted state on these nodes. It
+#   costs low-power H.264 encode QUALITY, nothing else; decode and encode both still work
+#   through the media engines. Grading it would put a permanent WARN on a configuration the
+#   operator has chosen.
+#   No host VAAPI userspace / no `vainfo` — NOT a defect. Plex ships its own libva and media
+#   driver inside its container, so the host needs neither. Flagging it would invite someone
+#   to `apt install vainfo` on a node to clear a health check, and this role installs nothing.
+#
+# The media ENGINES are the fact worth watching in this line: vcs* (video) and vecs*
+# (video-enhancement) are what a transcode actually runs on.
+- name: Assess — media engines, GuC/HuC firmware and host VAAPI userspace (informational)
+  ansible.builtin.set_fact:
+    node_health_checks: "{{ node_health_checks + [{
+      'id': 'graphics.media_stack',
+      'title': 'Media engines, GuC/HuC firmware and host VAAPI userspace (informational)',
+      'status': ('SKIP' if (node_health_render.display_devices | length) == 0 else 'INFO'),
+      'detail': media_detail }] }}"
+  vars:
+    ansible_become: false
+    g: "{{ node_health_facts.graphics }}"
+    r: "{{ node_health_render }}"
+    # `.get()` rather than a subscript: uc only carries the two Intel drivers, and a site
+    # that set the expected driver to amdgpu must get a clean "no such parameters" line
+    # instead of an undefined-key traceback.
+    guc: "{{ g.uc.get(node_health_graphics_expected_driver) }}"
+    guc_text: >-
+      {{ ('enable_guc=' ~ guc.enable_guc.value) if (guc is mapping and guc.enable_guc.value is not none)
+         else ('NOT READ — ' ~ (guc.enable_guc.reason | default('no reason recorded', true))
+               if guc is mapping
+               else 'no /sys/module/' ~ node_health_graphics_expected_driver ~ '/parameters at all') }}
+    media_detail: >-
+      {%- if (r.display_devices | length) == 0 -%}
+      no display-class PCI device on this machine, so there is no media engine, no GuC/HuC
+      firmware and nothing to transcode with.
+      {%- else -%}
+      media engines:
+      {{ (r.media_engines | join(', ')) if (r.media_engines | length) > 0
+         else 'NONE exposed under /sys/class/drm/card*/engine — a bound driver with no vcs*/vecs* engine cannot do media work' }}
+      (all engines: {{ (g.drm_cards | map(attribute='engines') | flatten | unique | sort | join(', ')) | default('none', true) }}).
+      GuC/HuC: {{ guc_text }}.
+      {{ ('Kernel cmdline carries ' ~ (g.cmdline_params | join(' '))) if (g.cmdline_params | length) > 0
+         else 'No i915/xe parameter on the kernel cmdline' }}.
+      GuC/HuC being off is a KNOWN, ACCEPTED state here and is never graded: it costs
+      low-power H.264 encode quality only, and both decode and encode still run on the
+      engines above.
+      Host VAAPI userspace: vainfo
+      {{ ('present at ' ~ node_health_facts.tools.vainfo) if node_health_facts.tools.vainfo
+         else 'NOT installed on this host' }}
+      — also never graded, because Plex ships its own libva and media driver inside its
+      container, so the host needs none. This role installs nothing.
+      {%- endif -%}
+
 # --- Thermals -----------------------------------------------------------------------
 - name: Assess — temperatures
   ansible.builtin.set_fact:

infra/ansible/roles/node_health/templates/summary.txt.j2

@@ -136,6 +136,37 @@
 {% endfor %}
 {% endfor %}
 
+--------------------------------------------------------------------------------
+ GRAPHICS / RENDER DEVICE (the Plex hardware-transcoding path)
+--------------------------------------------------------------------------------
+{% set gfx = node_health_facts.graphics %}
+{% if gfx.pci_display %}
+{% for p in gfx.pci_display %}
+ pci  {{ '%-12s' | format(p.address) }} {{ p.description | default(((p.vendor_id | default('?', true)) ~ ':' ~ (p.device_id | default('?', true)) ~ ' class ' ~ (p.class_id | default('?', true))), true) }}
+              driver {{ p.driver | default('NONE BOUND', true) }}
+{% endfor %}
+{% else %}
+ pci         no display-class device (PCI base class 0x03) on this machine — no GPU here
+{% endif %}
+{% for c in gfx.drm_cards %}
+ drm  {{ '%-12s' | format(c.card) }} driver {{ '%-8s' | format(c.driver | default('-', true)) }} at {{ c.pci_address | default('-', true) }}  engines {{ c.engines | join(' ') | default('none exposed', true) }}
+{% endfor %}
+{% if gfx.dri_present %}
+{% for d in gfx.devices %}
+ dev  {{ '%-12s' | format(d.name) }} {{ '%-18s' | format('character special' if d.char_device else 'NOT A CHAR DEVICE') }} mode {{ d.mode }}  {{ d.owner | default(d.uid, true) }}:{{ d.group | default('(gid unresolved)', true) }} gid {{ d.gid }}
+{% endfor %}
+{% else %}
+ dev         /dev/dri DOES NOT EXIST — no DRM device node on this node at all
+{% endif %}
+{# GID is printed, never asserted: `render` is a systemd dynamic allocation, so a rebuild may
+   legitimately move it and Plex's container init joins whichever group owns the device. See
+   defaults/main.yml (node_health_graphics_expected_driver) for the full reasoning. #}
+{% set guc = gfx.uc.get(node_health_graphics_expected_driver) %}
+ GuC/HuC     {{ ('enable_guc=' ~ guc.enable_guc.value) if (guc and guc.enable_guc.value is not none) else (('NOT READ — ' ~ (guc.enable_guc.reason | default('no reason recorded', true))) if guc else ('no /sys/module/' ~ node_health_graphics_expected_driver ~ '/parameters')) | regex_replace('\s+', ' ') | trim | wordwrap(64) | indent(14) }}
+             {{ ('kernel cmdline: ' ~ (gfx.cmdline_params | join(' '))) if gfx.cmdline_params else 'no i915/xe parameter on the kernel cmdline' }}
+ modules     {% for m, loaded in gfx.modules.items() %}{{ m }}={{ loaded | string | lower }}{{ ', ' if not loop.last }}{% endfor %} (/proc/modules — corroboration only; the bound-driver symlink above decides)
+ vainfo      {{ node_health_facts.tools.vainfo | default('NOT installed on this host — not a defect: Plex ships its own libva/media driver inside its container', true) }}
+
 --------------------------------------------------------------------------------
  PRESSURE STALL (/proc/pressure — % of wall time stalled)
 --------------------------------------------------------------------------------

platform/monitoring/alerts.yaml

@@ -839,6 +839,14 @@ spec:
         # that has never applied anything — or a GitRepository with no artifact yet — publishes the
         # series with no `revision` label. Without the matcher those group together under the empty
         # string and compare EQUAL, i.e. a never-applied Kustomization would read as converged.
+        #
+        # A THIRD THING THAT MUST NOT REGRESS — THE SEVERITY LABEL. These alerts are delivered
+        # because of the labels they do NOT carry as much as the ones they do. Do not "tidy" this
+        # pair by giving FluxRolloutInProgress a `severity`, and never `severity: info`: the chart's
+        # InfoInhibitor rule plus its `severity="info"` inhibit_rule suppress an info alert whenever
+        # it is the only thing firing in its namespace, which is every healthy deploy. Measured on
+        # prod 2026-09-30 — the alert fired correctly for 12 Kustomizations, resolved correctly, and
+        # was inhibited in between. The full reasoning is on the `notification: deploy` label below.
         # ===================================================================================
         - alert: FluxRolloutInProgress
           expr: |
@@ -857,7 +865,31 @@ spec:
           # `flux reconcile`, a change touching one Kustomization), and a deploy notification that
           # only sometimes arrives is worse than no notification at all.
           labels:
-            severity: info    # -> the email-deploy Alertmanager route; subject "[FLUX] applying/applied"
+            # ROUTED BY `notification`, AND DELIBERATELY CARRYING NO `severity` (fixed 2026-09-30).
+            # This alert originally used `severity: info`. That was WRONG, and wrong in the silent
+            # direction — measured on prod within minutes of the first real deploy.
+            # kube-prometheus-stack ships `general.rules` -> InfoInhibitor:
+            #     group by (namespace) (ALERTS{severity="info"} == 1)
+            #       unless on (namespace) group by (namespace)
+            #         (ALERTS{alertname!="InfoInhibitor", alertstate="firing", severity=~"warning|critical"} == 1)
+            # which fires for any namespace that has a firing info alert AND NOTHING ELSE WRONG in
+            # it; paired with the chart's inhibit_rule
+            #     source_matchers: [alertname="InfoInhibitor"]
+            #     target_matchers: [severity="info"]
+            #     equal: [namespace]
+            # the effect is that an info alert is suppressed EXACTLY WHEN it is the only thing
+            # happening in its namespace. For a deploy notification that is the only case that
+            # matters: on a healthy rollout of a healthy cluster, flux-system has no warning or
+            # critical alert, so InfoInhibitor fired and this alert never reached the receiver.
+            # Verified live: InfoInhibitor went active 2026-09-30T04:58:48Z, the same moment this
+            # alert began firing for 12 Kustomizations.
+            # Upstream's intent is explicit — `severity: info` means "only worth showing next to a
+            # real problem". A deploy notice is not that, so it must not claim that severity.
+            # `notification` is a label no inhibit_rule in the chart targets (all three match on
+            # severity values), and omitting `severity` also stops InfoInhibitor firing for
+            # flux-system at all. Route: platform/monitoring/kube-prometheus-stack.yaml matches
+            # `notification = "deploy"` -> the email-deploy receiver, subject "[FLUX] applying|applied".
+            notification: deploy
           annotations:
             summary: "Flux is applying a new revision — {{ $labels.name }} is behind main"
             description: "Kustomization {{ $labels.namespace }}/{{ $labels.name }} has applied {{ $labels.revision }}, which is not the revision the flux-system GitRepository has fetched from main. THIS MAIL MEANS A GIT CHANGE STARTED ROLLING OUT; the RESOLVED mail for this same alert means every Kustomization reached the new revision and the rollout is complete."

platform/monitoring/kube-prometheus-stack.yaml

@@ -139,11 +139,19 @@ spec:
             #
             # A DEDICATED ROUTE, because the default receiver is `email-warning`: without it a
             # routine deploy arrives subject-lined "[WARNING]" and becomes indistinguishable from a
-            # real platform fault, which is how alert mail stops being read at all. `severity: info`
-            # is used by NO other rule in this repo (grepped 2026-09-29: zero matches), so this
-            # route claims exactly the deploy notices and nothing else. Keep it that way — giving a
-            # genuine fault severity: info would silently route it here and re-label it a deploy.
-            - matchers: ['severity = "info"']
+            # real platform fault, which is how alert mail stops being read at all.
+            #
+            # MATCHES `notification`, NOT `severity` (corrected 2026-09-30). This route first read
+            # `severity = "info"`, which routed correctly and then had the mail SUPPRESSED before it
+            # was sent: the chart's own InfoInhibitor rule fires for any namespace holding a firing
+            # info alert with no warning/critical beside it, and its inhibit_rule
+            # (source alertname="InfoInhibitor" -> target severity="info", equal [namespace]) drops
+            # exactly that alert. A healthy deploy in a healthy flux-system is precisely that case,
+            # so the notification was inhibited on every occasion it was wanted. Measured live on
+            # prod 2026-09-30: InfoInhibitor went active at 04:58:48Z as the alert began firing.
+            # Routing on a non-severity label sidesteps all three of the chart's inhibit_rules,
+            # which match on severity values only. See the label's own comment in alerts.yaml.
+            - matchers: ['notification = "deploy"']
               receiver: email-deploy
               # One mail per ROLLOUT, not per Kustomization: the alert fires once per lagging
               # Kustomization (16 possible), and grouping on alertname alone collapses them into a

platform/monitoring/tests/flux-rollout.test.yaml

@@ -89,7 +89,7 @@ tests:
         alertname: FluxRolloutInProgress
         exp_alerts:
           - exp_labels:
-              severity: info
+              notification: deploy
               job: kube-state-metrics
               namespace: flux-system
               name: platform
@@ -148,7 +148,7 @@ tests:
         alertname: FluxRolloutInProgress
         exp_alerts:
           - exp_labels:
-              severity: info
+              notification: deploy
               job: kube-state-metrics
               namespace: flux-system
               name: platform
@@ -229,7 +229,7 @@ tests:
         alertname: FluxRolloutInProgress
         exp_alerts:
           - exp_labels:
-              severity: info
+              notification: deploy
               job: kube-state-metrics
               namespace: flux-system
               name: conformance