jakman85andClaude Opus 5
fdc4a7d9f4
During the substitution incident a bad render (k8sServiceHost: "") took down TWO of three
Cilium agents simultaneously. The agents' `config` init container falls back to the API
ClusterIP, which only the Cilium agent itself can translate — and that agent is the one
being replaced — so it deadlocks on `dial tcp 10.43.0.1:443: i/o timeout`.
Root cause of the 2-at-once: `updateStrategy.rollingUpdate.maxUnavailable: 2` is the
UPSTREAM CHART DEFAULT, confirmed by downloading cilium-1.20.1.tgz and reading
values.yaml:437-444 — not a local choice, and not overridden anywhere in this repo.
maxUnavailable: 1 makes a rollout replace ONE agent at a time and stop at the first pod
that fails to become Ready. The whole value of the setting is that the rollout halts on
the first bad node instead of taking the majority of the dataplane with it, and that
guarantee only exists at 1. It matters far more on a cold PROD bootstrap, where there is
no healthy peer to recover from — dev only self-healed because k3s-dev-3 kept a working
agent throughout.
Set as a [parity] field in ALL THREE places, per this repo's documented contract that the
Ansible bootstrap values and the Flux HelmRelease values must agree on settings that
define cluster networking (Ansible installs Cilium at bootstrap; the HelmRelease adopts
it; the two layers fight otherwise):
platform/cilium/helmrelease.yaml (authoritative for Flux)
infra/ansible/roles/cilium/templates/cilium-values.yaml.j2 (authoritative for bootstrap)
platform/cilium/values.yaml (reference mirror, kept in sync)
Verified by rendering the .j2 with roles/cilium/defaults and diffing full value sets: every
[parity] field is byte-equal across all three; only k8sServiceHost differs, as designed
(${K3S_API_HOST} vs {{ k3s_api_host }}).
MERGING THIS IS NON-DISRUPTIVE. updateStrategy lives at DaemonSet.spec.updateStrategy — a
SIBLING of spec.template (chart daemonset.yaml:49-53). The DaemonSet controller decides a
pod is out of date by hashing spec.template alone, so the pod-template hash does not move,
no new ControllerRevision is created, and zero pods are recreated. Helm patches the field
in place. (If it were disruptive it would be self-defeating: rolling agents under the old
maxUnavailable: 2 in order to install maxUnavailable: 1.) Verify after reconcile with
`kubectl -n kube-system get ds cilium -o jsonpath='{.spec.updateStrategy.rollingUpdate.maxUnavailable}'`
plus unchanged pod ages — that is the cleanest proof nothing rolled.
Trade-off recorded in the comments: upgrades serialise, roughly two waves to three at 3
nodes (a minute or two). On a large cluster this becomes painful and a percentage such as
"10%" would be right — noted so a future larger cluster revisits it deliberately.
SCOPE: this bounds blast radius, it does NOT close the substitution race. A bad render
still ships; it now breaks one node and stalls rather than taking the majority.
platform.dependsOn: [flux-system] (P0) is the fix for the cause.
Serves: R-PLAT-01, R-NET-01.
Co-Authored-By: Claude Opus 5 (1M context) <[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.