Files
home-network-k3s-impl/catalog/plex.yaml
jakman85andClaude Opus 5 0fee584e3a feat(plex): opt into hardware.gpu: intel-quicksync, and write the runbook for the step GitOps cannot reach
Plex has been transcoding in software on hardware that can do it in the iGPU. This
opts its ServiceDefinition into the `hardware` capability from #27 and re-renders.

catalog/plex.yaml gains four lines of YAML and the comment that explains them:

    hardware:
      gpu: intel-quicksync

which renders exactly two things into apps/wave-0/plex.yaml and nothing else — a
`dri` hostPath volume (/dev/dri, type: DirectoryOrCreate) and a read-write /dev/dri
volumeMount on the app container. Whole-tree render diff: 6 added lines, one file.

The comment records what is not obvious from the four lines: the device exists on
ALL THREE prod nodes with i915 bound (so no nodeSelector is rendered and none is
wanted); why `supplementalGroups` would be INERT rather than a hardening (the
image's cont-init hook adds the plex user to the device's group inside the
container, and s6-setuidgid then REPLACES the process group list from /etc/group,
discarding anything Kubernetes supplied); and why `DirectoryOrCreate` is
load-bearing (apps-wave-0 is wait:true with apps-wave-1 depending on it, so a
failed mount would stall the whole app tier for a feature that is not).

THE FEATURE IS INERT UNTIL A HUMAN CLICKS A BOX, and that is the part this commit
is really about. Mounting the device does not enable hardware transcoding; Plex's
`HardwareAcceleratedCodecs` preference does, and it is ABSENT from Preferences.xml
— the toggle has never been on. It cannot be automated: a bounded grep across the
running image's entire init surface (/etc/cont-init.d, /etc/services.d,
/etc/fix-attrs.d, /plex-common.sh, /usr/local/bin) found ZERO PLEX_PREFERENCE*
support, and the six setPref keys the image does write are all unrelated. So
runbooks/plex-quicksync.md is the procedure, registered in the configMapGenerator
(a runbook in git with no generator entry is reviewed, merged, and still a 404) and
indexed in runbooks/README.md. It covers the GitOps/manual boundary, the toggle and
the real preference keys (including the widely-cited one that does not exist and
the upstream misspelling nobody should "fix"), verification via `Transcode (hw)` on
the Plex dashboard — stated plainly as the ONLY proof, because Plex renders no
ServiceMonitor and an alert could never fire — the device-cgroup failure to expect
first with its Intel-device-plugin fallback, and the floating-`:latest` caveat.

Stacked on #27 (feat/sd-hardware-capability), which is open and unmerged; that
branch's commit is in this range by design and this must merge after it.

NOT VERIFIED, and the handoff says so at length: hardware transcoding has not been
observed working. Whether containerd's device cgroup lets a non-privileged pod
open() a bind-mounted char device is an open question that only deploying settles,
and the Plex-side toggle was still unset at the time of writing. A green gate
proves the manifest renders; it proves nothing about transcoding.

Gate (pinned toolbox, worktree): rc 3 — UNDETERMINED, not green. Passed:
decisions-log, lint, l0, render-golden, l1, approval-policy. Skipped (the known
local ceiling): spec-immutability (no sibling spec repo), gitea-settings (no
SETTINGS_API_TOKEN), conformance (CLUSTER_AVAILABLE unset, so L2/L3 did not run).
No fourth skip, nothing failed.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-10-01 21:05:17 -05:00

199 lines
15 KiB
YAML

# ServiceDefinition: plex
# Source of truth: spec docs/13-service-catalog.md, row 1 (the catalog's largest service).
# public | egress internet | config on Longhorn (metadata DB, DR-noncritical/reacquirable) |
# auth: native (Plex accounts, NOT Keycloak — docs/13 + docs/15 documented exception).
# Validates against schemas/servicedefinition.schema.json.
#
# BULK MEDIA — NOW ATTACHED (docs/04 bulk tier; the long-standing OQ-2 prerequisite, resolved for
# the STATIC case). The library is 8.33 T of ZFS on the Proxmox host at /mnt/Storage/plex, and it
# already exists: nothing is provisioned, an existing dataset is mounted. See
# docs/BULK-NFS-STORAGE.md for the layout, the export change and the uid analysis. (The bulk-tier
# requirement ID is deliberately still not typed here — see that document's "gate" note.)
name: plex
kind: container
source:
image: plexinc/pms-docker:latest
# plexinc/pms-docker env. Rendered VERBATIM onto the app container by render.py (schema env list).
env:
# PLEX_UID/PLEX_GID: the image boots as root (s6 PID1), chowns /config to this uid/gid, then drops
# the "Plex Media Server" process to it. 1000 matches the Longhorn ownership convention the other
# stateful apps use (seerr/semaphore run as UID/GID 1000), keeping the /config PVC writable by the
# dropped plex user. (Plex has no podSecurityContext/fsGroup — the image manages ownership itself.)
- name: PLEX_UID
value: "1000"
- name: PLEX_GID
value: "1000"
# TZ: no other service in the repo sets a timezone (repo-wide grep: none), so use the safe default.
- name: TZ
value: Etc/UTC
# ALLOWED_NETWORKS marks these CIDRs as trusted LAN, so in-cluster clients (Seerr -> plex:32400) are
# treated as local and NOT pushed onto Plex's remote-auth/relay path. 10.0.0.0/8 covers the Cilium
# pod CIDR (10.0.0.0/16, CLUSTER_POD_CIDR — Seerr's pod is 10.0.x.x) and the k3s service net
# (10.43.0.0/16); 192.168.0.0/16 covers the home LAN.
- name: ALLOWED_NETWORKS
value: 10.0.0.0/8,192.168.0.0/16
# PLEX_CLAIM — the ONE-SHOT plex.tv server claim, sourced from the SOPS Secret `plex-claim`
# (apps/wave-0/plex-claim-secret.sops.yaml, same wave => applied in the same reconcile as this
# workload). Plex cannot create libraries over the mounted bulk share while the server is
# UNCLAIMED, so this is wired; it was previously left out on the reasoning below, and only one
# half of that reasoning survived contact with the upstream source.
#
# A SHORT TTL IS THE OPERATIONAL CONSTRAINT, not a reason to abstain. A https://plex.tv/claim token
# expires in MINUTES — read the countdown the claim page renders; do not budget against a number
# written in this tree. (This comment previously asserted "~4 minutes" as established fact. It was
# UNCITED, upstream plexinc/pms-docker documents no expiry at all, and that number was load-bearing
# for the whole procedure design — including a since-disproven claim that the delivery pipeline was
# too slow to fit inside it. Measured 2026-09-29: the full loop is ~2m45s and fits.)
#
# The live token is injected by the operator inside that window, with an explicit `flux reconcile`
# to collapse the wait. Scripted end to end as infra/plex/claim-ship.sh; runbooks/plex-claim.md is
# the procedure. SERVER CLAIMED 2026-09-29 — this env is now a permanent no-op (see below), and the
# committed value is the spent token from that claim rather than the original placeholder.
#
# ONE-SHOT, AND SAFE TO SIT HERE EXPIRED. Verified from plexinc/pms-docker's own first-run script
# (branch `master`, root/etc/cont-init.d/40-plex-first-run, confirmed byte-identical to the file in
# the running `:latest` image), NOT assumed:
# - the exchange (line 106) is guarded on TWO conditions: PLEX_CLAIM non-empty AND the
# PlexOnlineToken pref in /config empty. Once claimed, the block is SKIPPED — this env is a
# no-op on every subsequent start, whatever it holds. (Upstream README: "If server is already
# logged in, this parameter is ignored.") The claim itself persists on the /config PVC as before.
# - an invalid/expired token on a still-unclaimed /config gets a 403 with an empty body; curl's
# status is unchecked, the token `sed` yields "", the success branch at line 120 does not fire,
# there is no `else` and no `exit 1`, and the script (no `set -e`) exits 0. It comes up UNCLAIMED and
# SERVING — it does NOT crashloop. The image also leaves S6_BEHAVIOUR_IF_STAGE2_FAILS at its
# default 0, which continues startup even when a cont-init script fails.
# So the earlier "a placeholder claim Secret would crashloop the pod" note was WRONG about the
# placeholder; it was right only about an ABSENT Secret. secretKeyRef here has no `optional` field,
# so the Secret must always exist in the Flux graph — which is why it is committed, encrypted, and
# listed in apps/wave-0/kustomization.yaml rather than hand-created at claim time. No schema change
# is needed: `optional` would only matter if a missing Secret had to be tolerated, and it doesn't.
- name: PLEX_CLAIM
valueFrom:
secretKeyRef:
name: plex-claim
key: PLEX_CLAIM
# ADVERTISE_IP ("Custom server access URLs") is DEFERRED, not accidentally omitted. It tells Plex
# which URL to advertise to plex.tv for REMOTE clients. The only candidate is
# https://plex.home.keithjackson.dev, but that host resolves via split-horizon DNS to the INTERNAL
# Gateway VIP (conformance/tests/l2-behavioral/dns-internal-resolution), and both its public
# reachability and whether the TLS-terminating Cilium Gateway proxies Plex's 32400 API correctly for
# remote access are UNVERIFIED. Advertising a wrong/internal-only URL breaks remote access for ALL
# clients, so per "prefer safety over completeness" it is left unset. FOLLOW-UP: once remote
# reachability through the Gateway is confirmed, set ADVERTISE_IP: "https://plex.home.keithjackson.dev:443".
# HARDWARE TRANSCODING — the host iGPU's render device (schema 1.8.0 `hardware`; R-PLAT-02).
# INTENT ONLY. This says "this workload needs an Intel Quick Sync render device"; it does NOT name a
# device path. The renderer currently satisfies it with exactly two things — a `/dev/dri` hostPath
# volume (`type: DirectoryOrCreate`) and a read-write `/dev/dri` volumeMount on the app container —
# and nothing else: no nodeSelector, no privileged, no resources (schemas/renderer-contract.md
# `### hardware`). If that mechanism is later replaced by the Intel GPU device plugin
# (`gpu.intel.com/i915`), it is a `catalog/render.py` change and THIS BLOCK DOES NOT MOVE. Do not
# "simplify" it into a raw `/dev/...` path; that is the whole point of the enum.
#
# THE DEVICE IS PRESENT ON EVERY PROD NODE, so nothing had to be installed and Plex can land
# anywhere. Measured on all three nodes 2026-09-30: `/dev/dri/renderD128` present, `root:render`,
# GID 992, mode 0660, driver `i915` bound (NOT `xe`), UHD Graphics 630 on an i7-9700T, media engines
# `vcs0`/`vecs0` live, iGPU enabled in BIOS on each. Plex happens to run on k3s-prod-2 today, but
# that is scheduler history rather than a requirement — this field deliberately renders no
# nodeSelector, because placement is a separate concern with its own justification.
#
# NO `podSecurityContext.supplementalGroups`, AND ADDING ONE WOULD BE INERT — do not "fix" this.
# The device is `root:render` 0660 and this process is uid/gid 1000, so the obvious move is to push
# the host `render` GID in as a supplemental group. It cannot work here. MEASURED IN THE RUNNING
# CONTAINER, 2026-09-30: the image's own
# `/etc/cont-init.d/45-plex-hw-transcode-and-connected-tuner` stats every char device under
# `/dev/dri`, `groupadd`s a matching group INSIDE the container when none exists, and
# `usermod -a -G`s the `plex` user into it — every start, nothing hardcoded, which also makes a host
# GID renumbering self-healing (no GID is pinned anywhere in this repo). The service then execs via
# `s6-setuidgid plex`, and `s6-setuidgid` REPLACES the process group list from `/etc/group` rather
# than appending to it: `Plex Media Server` runs with `Groups: 100 1000`, and root's gid `0` — which
# PID 1 (`s6-svscan`) does hold — is GONE. Anything Kubernetes supplies therefore reaches s6-svscan
# and is discarded before Plex ever starts. Mounting the device is sufficient; the group is the
# image's job and it does it correctly. `render.py --selftest` asserts the ABSENCE of a pod
# securityContext for this field precisely so nobody adds an inert one back later.
#
# `DirectoryOrCreate` IS THE SAFE FAILURE MODE, not laziness. A node that comes back without the
# device (rebuild, BIOS reset, driver regression, hardware swap) gets an empty directory and Plex
# degrades to SOFTWARE transcoding. `Directory` would fail the mount instead — and because
# `apps-wave-0` is `wait: true` with `apps-wave-1` `dependsOn` it, that would stall the WHOLE app
# tier for a feature that is not load-bearing. The price, stated plainly: a missing device is
# SILENT. This SD renders no `metricsEndpoint`, so there is no ServiceMonitor, no transcode-mode
# metric, and no alert that could ever fire. The only proof is an operator reading the Plex
# dashboard.
#
# THE LAST MILE IS A MANUAL OPERATOR STEP AND CANNOT LIVE IN THIS REPO. Mounting the device does
# not enable hardware transcoding — Plex's own `HardwareAcceleratedCodecs` preference does, and it
# is ABSENT from `Preferences.xml` today (the toggle has never been on). NO environment variable can
# set it: a grep of the running image's entire init surface (`/etc/cont-init.d`, `/etc/services.d`,
# `/etc/fix-attrs.d`, `/plex-common.sh`, `/usr/local/bin`) found ZERO `PLEX_PREFERENCE*` support,
# and the six prefs the image does write (`MachineIdentifier`, `ProcessedMachineIdentifier`,
# `PlexOnlineToken`, `customConnections`, `allowedNetworks`, `TranscoderTempDirectory`) are all
# unrelated. So there is no GitOps path to the toggle; an operator clicks it once in the web UI.
# `runbooks/plex-quicksync.md` is that procedure, plus how to verify it took and the
# device-cgroup failure mode to expect first.
hardware:
gpu: intel-quicksync
exposure: public # edge port-forward + public DNS; clients + Seerr reach it (docs/09; R-DNS/R-NET)
egress: internet # normal WAN egress (docs/03; R-NET-05)
storage:
- name: config
size: 8Gi
class: longhorn # Plex DB/metadata: replicated app state on the 3-replica tier (docs/04; R-STATE-01/02)
mountPath: /config # plexinc/pms-docker writes its identity/claim + "Library" DB under /config, NOT the
# renderer default /data/config. Without this the PVC sat unused and Plex wrote to the
# container's EPHEMERAL layer -> unclaimed + all state lost on restart. The image inits as
# root (s6-svscan PID 1), chowns /config to the plex user, then drops -> no fsGroup needed
# (verified in-cluster: PID1=root, "Plex Media Server"=plex). Persisting /config here also
# makes the claim survive restarts once claimed — which is what makes the PLEX_CLAIM env
# above a ONE-SHOT: the token is exchanged for a PlexOnlineToken written here, and the
# exchange is then skipped on every later start. (The older note here claimed a
# placeholder claim Secret "would crashloop the pod"; upstream's first-run script says
# otherwise — see the PLEX_CLAIM comment in `env` above. An ABSENT Secret is the hard
# failure, and that is why one is committed.)
# THE LIBRARY (docs/04 bulk tier). One READ-ONLY mount of the export ROOT, giving /media/movies,
# /media/tv and /media/photos — the whole tree the layout actually has (`ls /mnt/Storage/plex`:
# downloads/ movies/ photos/ tv/).
#
# WHY THE ROOT AND NOT THREE subPath MOUNTS. Nothing is gained by narrowing: the mount is `ro`,
# so no subPath could remove a privilege that matters, while three mounts would triple the NFS
# mounts per pod and mean a manifest change every time a top-level library is added.
#
# WHY READ-ONLY, when the export is `rw` and the other consumers write. Plex is a SERVER: it
# indexes and streams. Every write on that tree belongs to Sonarr and Radarr. Marking it here
# costs nothing and removes Plex from the set of things that can damage 8.33 T. Enforced by the
# PV's nfs.readOnly (a real `ro` mount), not only by the volumeMount flag.
#
# UID: no change needed. The tree is 0755 owned 1000:3000 throughout, so it is world-readable and
# world-traversable, and PLEX_UID/PLEX_GID above already make the process uid 1000 in any case.
# (fsGroup would have been a no-op here regardless — the in-tree NFS plugin does no ownership
# management. That is the trap the arrs' PUID/PGID exists to avoid; Plex never hits it.)
- name: media
class: bulk
export: /mnt/Storage/plex # the ZFS dataset Storage/plex, on ${BULK_NFS_SERVER}
mountPath: /media
readOnly: true
size: 9Ti # ADVISORY ONLY (nothing enforces a static NFS PV's capacity): the
# dataset's 8.33 T used, rounded up, so `kubectl get pv` reports
# something true. The real limit is the ZFS pool.
dependencies: [] # default-deny: reaches only DNS; clients/Seerr reach IT (docs/03; R-NET-01/02)
ingressRoutes:
- host: plex.${BASE_DOMAIN}
port: 32400 # Plex web UI + API served on 32400 (wildcard TLS at the Gateway; docs/08/09)
auth:
mode: native # Plex account auth — documented exception, NOT Keycloak (docs/13/15; R-IDP-02)
update:
channel: stable # R-UPD-01 (never pre-release)
range: ">=1.40.0" # acceptable versions (advisory; image-automation off during onboarding)
cadence: "0 4 * * 0" # weekly stable check/apply
autoRollbackOnFailedHealth: true # R-UPD-03
observability:
metrics: true
slis:
- up # R-OBS-01: service-down alert
backup:
# The config volume is on the longhorn (replicated, "irreplaceable") tier, so the L0 Kyverno
# backup policy (R-STATE-03) forbids `reacquirable` here — it must reference an off-cluster
# schedule. Plex's metadata DB (library index, thumbnails, watch state) is expensive to rebuild,
# so it is backed up off-cluster. The bulk library itself, once attached, is the `reacquirable`
# part (docs/04) and is NOT covered by this schedule.
policy: daily-offcluster # off-cluster backup of the longhorn config volume (docs/04; R-STATE-03)