jakman85andClaude Opus 5
505083fded
`instances: 3` + `podAntiAffinityType: required` fixed the INSTANCE spread but moved
the PRIMARY concentration from k3s-prod-2 to k3s-prod-1: all three primaries
(keycloak-db-2, nextcloud-db-2, semaphore-db-2) ended up on one node, so losing it
meant three simultaneous failovers.
There is NO declarative fix, established from the CRD installed on prod (CNPG 1.30.0,
clusters.postgresql.cnpg.io/v1) rather than from memory. Every spec.affinity field and
spec.topologySpreadConstraints applies to "all the cluster's pods" and is not role-aware;
spec.replica.primary names a Cluster object in a distributed topology, not a node;
primaryUpdateMethod/switchoverDelay/primaryLease govern how a promotion happens, never
where. `targetPrimary` exists only under STATUS, never spec — so `cnpg promote` is an
imperative status patch by construction and there is nothing to put in git. The obvious
workaround is worse than nothing: pod anti-affinity is only ever
...IgnoredDuringExecution while CNPG promotes by relabelling a RUNNING pod, and with
3 instances on 3 nodes it would leave the third instance unschedulable.
So this commits the part that IS durable — visibility — and rebalances live.
CNPGPrimariesCoLocated joins CNPG's own answer to "who is primary" (the <cluster>-rw
Service selects only the primary) against the node: kube_endpointslice_endpoints carries
endpoint_nodename + targetref_name, which two label_replaces lift into node/pod. Neither
family works alone — cnpg_* metrics have no node label, and kube_pod_labels is EMPTY here
(no kube-state-metrics label allowlist), so cnpg.io/instanceRole is not in Prometheus at
all. `* on (namespace, pod) group_left () cnpg_collector_up` keeps an unrelated `*-rw`
Service from triggering it, and uses the one metric present for EVERY instance rather than
the cnpg_pg_stat_* family that is missing for nextcloud-db.
A Ready-node gate stops this becoming another permanently-firing alert: with three
clusters on three nodes a node loss NECESSARILY co-locates two primaries, so the rule
only speaks when the spread is actually achievable, and re-arms when the node returns.
Proven both ways. Live: the expr returned {node="k3s-prod-1"} => 3 before, empty after,
with the inner join still resolving all three primaries (quiet because false, not blind);
loaded into prod's Prometheus as a throwaway `for: 1m` twin it went pending at +70s and
firing at +130s. alerts.promtool-test.yaml pins four cases under promtool 3.14.0 (the
exact version prod runs) and is mutation-checked — dropping the join, dropping the gate
or shortening `for:` each makes a test FAIL.
Rebalanced live, one cluster at a time: keycloak-db -> k3s-prod-2, nextcloud-db ->
k3s-prod-3, semaphore-db deliberately LEFT on k3s-prod-1 (lightest writer, and that node
has the known etcd/Longhorn I/O contention) — two switchovers, not three. Write outage
measured with a `select txid_current()` probe, not estimated: 9.4s and 9.43s, one
contiguous burst each. All three back to readyInstances: 3 with
synchronous_standby_names = ANY 1 (...) and both standbys streaming/quorum.
The placement is CURRENT, NOT DURABLE, and the alert is the point: the next failover or
rolling update can re-concentrate the primaries, and now that gets reported instead of
discovered by hand.
Co-Authored-By: Claude Opus 5 <[email protected]>
platform/
Cluster-wide platform services, Flux-managed (R-PLAT-01, R-GITOPS-01/02/03). Reconciled
by the platform Flux Kustomization defined in clusters/base/platform.yaml,
before apps/.
Governing spec: docs/05-gitops-and-delivery.md,
docs/01-architecture-overview.md.
Phase 0 scaffolding only. Every component here is a structurally-correct stub — a Flux HelmRelease and/or Kustomization with a values placeholder, a README citing the governing ADR/spec, and TODOs for the phase that fills it in. No cluster exists; nothing reconciles yet. Do not add working config, secrets, or provisioning under Phase 0 (spec
AGENTS.md§1/§5/§6,roadmap/phases.md).
Reconciliation flow (how a change lands)
git (source of truth)
│ operator PR → CI (lint · schema · Kyverno L0 · Chainsaw) → merge to tracked branch
▼
Flux GitRepository (clusters/base/flux-system.yaml)
▼
Flux Kustomization "platform" → ./platform (this dir) ── substituteFrom cluster-vars ──┐
│ prune=true (drift correction, R-GITOPS-03) · wait=true │ R-ENV-02
▼ │
Flux Kustomization "apps" → ./apps (dependsOn platform) ─ substituteFrom cluster-vars ──┘
Git is authoritative; the cluster conforms to git and drift is auto-corrected (R-GITOPS-01/03).
Manual kubectl apply of platform state is prohibited (spec AGENTS.md §5).
The dev ↔ prod overlay model (R-ENV-02)
Platform manifests are authored once. Every value that legitimately differs between environments
is a ${TOKEN} resolved from the cluster-vars ConfigMap via Flux postBuild.substituteFrom. The
clusters/dev and clusters/prod overlays differ only by the values they patch into
cluster-vars (issuer, replica counts, storage sizes, retention). See
clusters/README.md. Base manifests are never forked per environment.
Components (one directory each)
| Dir | Component | Governing ADR / spec | Serves |
|---|---|---|---|
cilium/ |
CNI + kube-proxy replacement + Gateway API + Egress Gateway + Hubble | ADR-0002, docs/03 | R-NET-* |
longhorn/ |
Replicated block storage; 3-replica default StorageClass + bulk tier | ADR-0003, docs/04 | R-STATE-* |
cert-manager/ |
TLS via Let's Encrypt DNS-01 (Cloudflare); staging + prod ClusterIssuers | ADR-0006, docs/08 | R-TLS-* |
externaldns/ |
Automatic DNS records for public services (Cloudflare) | docs/09 | R-DNS-* |
gateway/ |
Gateway API GatewayClass + shared HTTPS Gateway + wildcard cert | ADR-0002/ADR-0006, docs/09 | R-DNS-01, R-TLS-01 |
monitoring/ |
kube-prometheus-stack + Loki + Grafana Alloy + Alertmanager | docs/10 | R-OBS-* |
velero/ |
Off-cluster backup/DR of volumes + resource state | ADR-0003, docs/04 | R-STATE-03 |
kubevirt/ |
KubeVirt + CDI (IaaS: application VMs on the same K8s surface) | ADR-0005, docs/06 | R-PLAT-03 |
image-automation/ |
Flux image-update-automation (hands-off image tag advance) | ADR-0009, docs/11 | R-UPD-02 |
keycloak/ |
Platform IdP (OIDC + SAML), config-as-code, PostgreSQL on Longhorn | ADR-0014, docs/15 | R-IDP-* |
oauth2-proxy/ |
Forward-auth at the Gateway for non-OIDC apps → Keycloak | ADR-0014, docs/15 | R-IDP-* |
kyverno/ |
L0 policy-as-code gate — OWNED BY THE POLICY ENGINEER (WS-TEST). | ADR-0011, docs/14 | R-TEST-* |
⚠️ INTEGRATION TODO(PM): wire kyverno into the platform kustomization
platform/kyverno/ is authored by a different agent (the policy engineer, WS-TEST). This
workstream did not create any files under platform/kyverno/ and must not.
platform/kustomization.yaml intentionally omits - kyverno. Once the
policy engineer's files land, the PM must add - kyverno to that list (recommended first, so
policies are present before other components reconcile). The line is present as a commented TODO in
the kustomization.
Secrets
Every secret referenced below (Cloudflare API token, Velero backup-target creds, Keycloak admin/DB, oauth2-proxy cookie/client secrets) is referenced by name only and will be committed SOPS-encrypted (WS-SEC, ADR-0007). No plaintext secret appears anywhere in this tree.
Cross-workstream contracts surfaced by these stubs
- cilium (WS-NET ↔ WS-INFRA): Cilium's initial CNI install is done by Ansible at cluster bootstrap (docs/02, Phase 1). The HelmRelease here manages Cilium config thereafter; its Helm values MUST match the Ansible bootstrap values (kubeProxyReplacement, k8sServiceHost/Port, API server host) or reconciliation will fight the bootstrap. Contract owner: WS-NET + WS-INFRA.
- gateway + cert-manager + externaldns (WS-NET + WS-SEC): the shared Gateway listener, the
wildcard
*.home.keithjackson.devcert, and the ExternalDNS source all reference each other; they form the "Issuer + Gateway TLS" interface inroadmap/workstreams.md. - image-automation (WS-UPDATE): this dir holds only the cluster-wide ImageUpdateAutomation +
git write-back. Per-service
ImageRepository/ImagePolicyare rendered from each ServiceDefinition'supdateblock (WS-GITOPS/WS-UPDATE), living withapps/. - keycloak/oauth2-proxy (WS-SEC): the SSO/auth contract (
authblock → Keycloak client / oauth2-proxy protection) is owned by WS-SEC; these are placeholders pending that contract.