feat(cloudflared): Cloudflare Tunnel connector, Phase 1 (isolated, no traffic change)

Adds platform/cloudflared: a locally-managed tunnel whose ingress rules live in git. LAN/VPN-only hosts (plex, plex-vip, jackett, pihole, pihole-dns, semaphore, qbittorrent, radarr, sonarr, headlamp, unifi, crafty-mc) map to 404. The apex and *.home go to cilium-gateway-shared.gateway over TLS with matchSNItoHost. Last comes a catch-all 404. Nothing routes to the Kubernetes API. - 2-replica Deployment, hard node spread, non-root, pinned digest, PDB - default-deny plus an egress CNP: Cloudflare edge 7844/443, the Gateway, and Gateway backends by gateway-access=shared minus the LAN-only namespaces (needed because of the CVE-2025-30162 L7LB egress re-check) - PodMonitor plus two alerts that fire on absent series, with promtool tests - its own Flux Kustomization (dependsOn platform-config, wait:false, nothing depends on it), plus SOPS decryption patches in both overlays - placeholder credentials (SOPS-encrypted) so it can merge before enrolment - L0 cloudflared-ingress-rules, and a cloudflared_ scrape owner - runbooks/cloudflare-tunnel.md and decisions/2026-11-08-cloudflare-tunnel.md Co-Authored-By: Claude Opus 5.5 <[email protected]>
2026-11-08 12:38:22 -06:00
1 parent eb62c13c6b
commit aabc8c60b6
@@ -0,0 +1,61 @@
+---
+# Flux Kustomization: Cloudflare Tunnel connector — reconciles ./platform/cloudflared.
+#
+# ISOLATION IS THE POINT OF THIS FILE. The Deployment it applies CANNOT become Ready until the
+# operator enrols the tunnel (runbooks/cloudflare-tunnel.md): it ships with REPLACE-ME credentials
+# and a placeholder UUID, and a wrong or revoked credential later produces the same state. So:
+#
+#   * ITS OWN Kustomization, not a line in platform/kustomization.yaml. `platform` is wait:true and
+#     gates platform-config, which gates every apps wave; an unenrolled tunnel there would be a
+#     platform-wide stall ON MERGE, with the cause (a missing manual step) invisible from any Flux
+#     condition. Same reasoning, and same failure shape, as vpn-ingress's unfilled server key.
+#   * wait: false. Its pods are legitimately not-Ready whenever the credentials are absent or the
+#     edge is unreachable. Health is reported by the CloudflaredTunnelDown / ReplicasDegraded
+#     alerts (platform/cloudflared/alerts.yaml), not by this Kustomization's Ready condition —
+#     which reaches Ready on APPLY success.
+#   * NOTHING dependsOn THIS, and nothing should. A missing or invalid credentials Secret can then
+#     only ever affect the tunnel itself. conformance/tests/l0-static/cloudflared-ingress-rules
+#     fails the gate if any Kustomization gains `dependsOn: cloudflared`, or if this one stops
+#     being wait:false.
+#   * No Certificate, no HelmRelease, no CRD: nothing in the path for Flux's health checks to wait
+#     on even if wait were flipped (the Certificate-stall lesson).
+#
+# dependsOn: [platform-config] — A REAL EDGE.
+#   1. CRD ORDERING: PodMonitor and PrometheusRule are monitoring.coreos.com CRs whose CRDs are
+#      installed by kube-prometheus-stack in `platform`; platform-config dependsOn platform, so this
+#      edge carries that guarantee transitively (Flux aborts a whole pass on an unknown kind).
+#   2. THE FAR SIDE OF THE TUNNEL: the Gateway (and so the cilium-gateway-shared Service the ingress
+#      rules point at) is applied by platform-config. A tunnel that comes up before its origin is a
+#      support call.
+#
+# ZERO EFFECT ON LIVE TRAFFIC UNTIL DNS MOVES. Cloudflare only sends a hostname through a tunnel
+# when that hostname's DNS record is a CNAME to <uuid>.cfargotunnel.com. This change creates no
+# such record and leaves external-dns, the Gateway annotations, Pi-hole and CoreDNS untouched.
+apiVersion: kustomize.toolkit.fluxcd.io/v1
+kind: Kustomization
+metadata:
+  name: cloudflared
+  namespace: flux-system
+spec:
+  interval: 10m
+  retryInterval: 2m
+  timeout: 5m
+  prune: true
+  wait: false
+  dependsOn:
+    - name: platform-config
+  sourceRef:
+    kind: GitRepository
+    name: flux-system
+  path: ./platform/cloudflared
+  # REQUIRED, not boilerplate: platform/cloudflared/config.yaml renders `${BASE_DOMAIN}` into every
+  # ingress hostname, and alerts.yaml into both runbook_url annotations. Without this block the
+  # token becomes the EMPTY STRING and the Kustomization still reports Ready (substitution fails
+  # OPEN), leaving ingress rules for `plex.` and `*.` — a tunnel that 404s everything at best.
+  postBuild:
+    substituteFrom:
+      - kind: ConfigMap
+        name: cluster-vars
+  # SOPS decryption is layered per-environment: clusters/dev and clusters/prod each patch THIS
+  # Kustomization by name with a `decryption:` stanza for cloudflared-credentials.sops.yaml.
+  # Without it the Secret applies cleanly full of ENC[...] and cloudflared cannot authenticate.
@@ -78,6 +78,13 @@ resources:
  # `wg-server-key` Secret, so in the gating `platform` tier an unfinished manual step would have
  # stalled every apps wave. Carries no SOPS secret, so neither overlay adds a decryption patch.
  - vpn-ingress.yaml     # Flux Kustomization -> ./platform/vpn-ingress (dependsOn platform-config)
+  # Cloudflare Tunnel connector (north-south INGRESS from the Cloudflare edge) — POST-platform tier
+  # (dependsOn platform-config, wait:false), and NOTHING dependsOn it. Non-gating is load-bearing,
+  # as for vpn-ingress: the Deployment cannot become Ready until the operator enrols the tunnel
+  # (runbooks/cloudflare-tunnel.md), so in a gating tier an unfinished manual step — or a revoked
+  # credential later — would stall every apps wave. Carries cloudflared-credentials.sops.yaml, so
+  # both overlays add a SOPS decryption patch for it (by name). See clusters/base/cloudflared.yaml.
+  - cloudflared.yaml     # Flux Kustomization -> ./platform/cloudflared (dependsOn platform-config)
  # PM agent — reads Gitea issues and runs one worker agent per assignment that authors a
  # change, gates it and opens a pull request. POST-APP tier (dependsOn apps-wave-0,
  # wait:false): what it needs is GITEA, not Keycloak or the Gateway, and it must never gate
@@ -140,6 +140,23 @@ patches:
          provider: sops
          secretRef:
            name: sops-age
+  # cloudflared (the Cloudflare Tunnel connector, clusters/base/cloudflared.yaml) carries
+  # platform/cloudflared/cloudflared-credentials.sops.yaml — the tunnel credentials JSON, the one
+  # secret in that component. Without this stanza the Secret applies full of ENC[...]: the APPLY
+  # SUCCEEDS, the Kustomization stays Ready, and the only symptom is a connector that cannot
+  # authenticate to the edge (CloudflaredTunnelDown fires). The `sops-age` Secret is out-of-band
+  # (name only).
+  - patch: |-
+      apiVersion: kustomize.toolkit.fluxcd.io/v1
+      kind: Kustomization
+      metadata:
+        name: cloudflared
+        namespace: flux-system
+      spec:
+        decryption:
+          provider: sops
+          secretRef:
+            name: sops-age
  # pm-agent (the Program Manager agent service, clusters/base/pm-agent.yaml) carries
  # pm-agent-credentials.sops.yaml — the Gitea write token for the dedicated non-admin bot
  # account and the Anthropic subscription token from `claude setup-token`. Without this
@@ -131,6 +131,23 @@ patches:
          provider: sops
          secretRef:
            name: sops-age
+  # cloudflared (the Cloudflare Tunnel connector, clusters/base/cloudflared.yaml) carries
+  # platform/cloudflared/cloudflared-credentials.sops.yaml — the tunnel credentials JSON, the one
+  # secret in that component. Without this stanza the Secret applies full of ENC[...]: the APPLY
+  # SUCCEEDS, the Kustomization stays Ready, and the only symptom is a connector that cannot
+  # authenticate to the edge (CloudflaredTunnelDown fires). The `sops-age` Secret is out-of-band
+  # (name only).
+  - patch: |-
+      apiVersion: kustomize.toolkit.fluxcd.io/v1
+      kind: Kustomization
+      metadata:
+        name: cloudflared
+        namespace: flux-system
+      spec:
+        decryption:
+          provider: sops
+          secretRef:
+            name: sops-age
  # pm-agent (the Program Manager agent service, clusters/base/pm-agent.yaml) carries
  # pm-agent-credentials.sops.yaml — the Gitea write token for the dedicated non-admin bot
  # account and the Anthropic subscription token from `claude setup-token`. Without this