Files
home-network-k3s-impl/platform/keycloak
jakman85 cac413e87a
gate / gate (push) Has been cancelled
gate / conformance (push) Has been cancelled
feat(cnpg): synchronous replication, quorum of 1, dataDurability preferred
Three instances replicating ASYNCHRONOUSLY still lose data on failover: COMMIT
returns as soon as the primary has flushed locally, so a primary that dies
before its standbys catch up takes the last few transactions with it and the
promoted standby comes up quietly missing them. On keycloak-db that is a
just-created user, a rotated credential or a consent vanishing at exactly the
moment of a failover.

`method: any` + `number: 1` makes COMMIT wait for ONE of the two standbys to
confirm — the point of having them.

dataDurability: preferred, NEVER required. `required` is a strict quorum:
fewer than `number` healthy standbys and writes BLOCK. Postgres here shares
three nodes with etcd and the CNI, so one degraded standby — a node reboot, a
Longhorn replica rebuild, a Cilium restart — would turn a partial degradation
into a total write outage, and on the SSO database that takes kubectl OIDC,
Grafana, Headlamp, Gitea and forward-auth with it. `preferred` keeps
synchronous commit while a healthy standby is there and relaxes the required
count dynamically when one is not. dataDurability is only honoured while
standbyNamesPre/standbyNamesPost are unset — both are.

NON-DISRUPTIVE: this compiles to `synchronous_standby_names`, a reload-only
PostgreSQL parameter. No pod restart, no switchover, no client disconnect.
It is the last of the three commits because it wants standbys that already
exist and are already on their final nodes.

Field shape verified against the live clusters.postgresql.cnpg.io CRD before
relying on it (CNPG 1.30.0, byte-identical schema on k3s-prod and k3s-dev):
spec.postgresql.synchronous requires `method` (enum any|first) and `number`
(x-kubernetes-validation self > 0); `dataDurability` is enum required|
preferred. None of the three Clusters previously had a `postgresql:` block,
so this adds one rather than merging into existing parameters.

DEV IMPACT: identical and non-disruptive, same reload-only path.

Verified: yamllint clean; both tiers render the block.

Co-Authored-By: Claude Opus 5 <[email protected]>
(cherry picked from commit f1ce19461415e77eb2f1ca5109ebab49edf0860b)
2026-09-07 23:54:19 -05:00
..
2026-08-24 19:52:25 -05:00

platform/keycloak

Keycloak — the platform Identity Provider (SSO via OIDC + SAML), onboarded early (Phase 6 IdP).

Image / tooling strategy (F-KY1 landmine avoided)

The original stub used the Bitnami Keycloak chart + bundled Bitnami PostgreSQL. Bitnami's free Docker Hub images were purged (DECISIONS-LOG F-KY1) → that path ImagePullBackOffs. Replaced with:

  • Keycloak: the official Keycloak Operator (quay.io/keycloak/keycloak-operator + quay.io/keycloak/keycloak, v26.0.6) driving a Keycloak CR + a KeycloakRealmImport CR for config-as-code (ADR-0014 permits Operator OR Helm; Operator gives clean CR-driven realm reconcile).
  • Database: CloudNativePG (ghcr.io/cloudnative-pg, see ../cnpg) — a Cluster on the 3-replica longhorn StorageClass (DR-critical, R-IDP-05), with declarative backup hooks.

quay.io + ghcr.io are unaffected by the Bitnami purge. Operator manifests are pinned upstream release files pulled as remote kustomize bases (the kubevirt-stub pattern); Renovate maintains the version.

Layout (controllers / configs split — F-MON1)

File Applied by What
kustomization.yaml (namespace, operator CRDs+Deployment, admin secret, dashboard) platform controllers
keycloak-instance.yaml (Keycloak CR, ${KEYCLOAK_REPLICAS}) platform-config config
postgres-cluster.yaml (CNPG Cluster on longhorn) platform-config config
keycloak-realm-import.yaml (KeycloakRealmImport: realm/groups/clients/MFA) platform-config config
client-secret-reconciler.yaml (CronJob: client secrets ← git, every 15m) platform-config config
httproute.yaml (keycloak.home.keithjackson.dev) platform-config config
servicemonitor.yaml (Prometheus scrape) platform-config config

Realm config (groups platform-admins/media-users/viewers, OIDC clients grafana+oauth2-proxy, brute-force ON, and a conditional MFA browser flow that REQUIRES OTP for platform-admins, R-IDP-04) reconciles purely from git — no console clicking (R-IDP-03).

Admin credential + break-glass (R-IDP-04 / R-IDP-05)

The provisioned keycloak-admin-credentials.sops.yaml (keys admin-user/admin-password) is injected as the temporary bootstrap/break-glass admin via KC_BOOTSTRAP_ADMIN_* env (podTemplate escape hatch) — this consumes the secret as provisioned, without re-keying it (the operator's native bootstrapAdmin wants username/password keys, which would require editing the encrypted file). The Keycloak bootstrap admin is the documented break-glass path so an IdP/SSO outage does not lock the operator out (ADR-0014); Grafana likewise keeps its local admin login until SSO is proven.

Operator hand-offs (fill before / during deploy)

  1. keycloak-realm-clients.sops.yaml (keycloak ns) — from .sops.yaml.example. One <clientId>-client-secret key per confidential client, openssl rand -hex 32 each. The realm import injects them into the Keycloak clients via spec.placeholders. Add to kustomization.yaml once filled. The key name MUST be <clientId>-client-secret — the reconciler below derives the clientId from it, and CI rejects any other name. (This step used to read "the realm import stays PENDING until this exists". It does not — see the next section. That false belief is what allowed the 2026-09-06 outage.)
  2. ../oauth2-proxy/oauth2-proxy-credentials.sops.yaml (oauth2-proxy ns) — client-id: oauth2-proxy, client-secret = the SAME oauth2-proxy-client-secret above, cookie-secret = openssl rand -base64 32.
  3. ../monitoring/grafana-oidc-credentials.sops.yaml (monitoring ns) — client-secret = the SAME grafana-client-secret above.

(Cross-namespace Secrets can't be shared, so each client secret is stored twice — once for the realm import in keycloak, once for the consuming app.) See the two .sops.yaml.example templates for the exact keys + steps. No plaintext secret is ever committed.

Client secrets: the realm import fails OPEN, so a reconciler owns them (2026-09-06)

The realm import is a one-shot that fails open. Measured on both clusters:

  • When the operator cannot resolve a $(env:...) placeholder it stores the literal placeholder text as the client secret — and the import Job still exits 0. There is no PENDING state, no error condition, and HasErrors stays False.
  • Once complete the CR rests at Done=True / Started=False and never re-runs, so a Secret key added later is never picked up.

Together those produced a total SSO outage on prod (all 12 clients holding the literal placeholder; every login rejected with "Invalid client or Invalid client credentials") and a single broken client on dev (oauth2-proxy, whose key was added after dev's import had already completed). Every cluster signal was green throughout, including the conformance test that asserts Done=True.

Three layers now cover it:

Layer Where What it does
Prevent conformance/tests/l0-static/keycloak-client-secret-reconciler (runs on every merge, unconditionally, from ci/l0.sh) Every placeholder is defined, reads keycloak-realm-clients, and names an existing key called <clientId>-client-secret; public clients declare no secret; and the Flux Kustomization applying the Secret is a real transitive dependsOn ancestor (wait: true) of the ones applying the import and the reconciler. A missing SOPS key is now unmergeable.
Heal client-secret-reconciler.yaml — CronJob, every 15m Compares each client's stored secret with the mounted keycloak-realm-clients value and PUTs the minimal {clientId, secret} representation only where they differ. Skips correct clients, never logs a secret, holds a hard endpoint allow-list so users/groups/roles/flows are unreachable, and needs no Kubernetes API access (automountServiceAccountToken: false).
Detect conformance/tests/l2-behavioral/keycloak-client-secrets-match-git + alerts KeycloakClientSecretReconcilerFailing / …Stale Runs the same script in read-only --audit mode against the live realm and fails on any mismatch or literal placeholder; the alerts make the reconciler's silence observable in prod.

The reconciler's own --selftest (run by the L0 gate, which extracts the script from the shipped ConfigMap) proves compare-then-write, idempotence (zero writes on a converged realm), no-secret-logging, the endpoint allow-list, and fail-closed behaviour.

Manual repair / one-off run (the CronJob normally does this):

kubectl -n keycloak create job --from=cronjob/keycloak-client-secret-reconciler kc-fix-$(date +%s)
kubectl -n keycloak logs -l app.kubernetes.io/name=keycloak-client-secret-reconciler --tail=-1

What the reconciler does NOT fix: anything other than client secrets. A NEW client, a changed redirect URI or a new protocol mapper still needs the realm import to actually re-run (it will not on its own) or a deliberate admin-API/kcadm change. Done=True is never evidence that a realm edit landed.

Exceptions that keep native auth (do not force SSO) — ADR-0014

Plex/Seerr (Plex auth), Minecraft (Mojang/Microsoft), UniFi (native).