home-network-k3s-impl/apps/wave-0/pihole.yaml

---
# Namespace (trust zone; default-deny + policies apply)
apiVersion: v1
kind: Namespace
metadata:
  name: pihole
  labels:
    homelab.keithjackson.dev/app-namespace: 'true'
    gateway-access: shared
  annotations:
    homelab.keithjackson.dev/backup-policy: daily-offcluster
---
# Default-deny baseline (R-NET-01): deny all, allow only DNS
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: default-deny
  namespace: pihole
  labels:
    homelab.keithjackson.dev/baseline: default-deny
spec:
  podSelector: {}
  policyTypes:
  - Ingress
  - Egress
  ingress: []
  egress:
  - to:
    - namespaceSelector:
        matchLabels:
          kubernetes.io/metadata.name: kube-system
    ports:
    - protocol: UDP
      port: 53
    - protocol: TCP
      port: 53
---
# StatefulSet (R-PLAT-02)
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: pihole
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  replicas: 2
  serviceName: pihole
  podManagementPolicy: Parallel
  selector:
    matchLabels:
      app.kubernetes.io/name: pihole
  template:
    metadata:
      labels:
        app.kubernetes.io/name: pihole
        homelab.keithjackson.dev/egress-class: internet
        homelab.keithjackson.dev/auth-mode: forward-auth
      annotations:
        homelab.keithjackson.dev/auth-mode: forward-auth
        homelab.keithjackson.dev/auth-groups: platform-admins
    spec:
      containers:
      - name: pihole
        image: pihole/pihole
        ports:
        - containerPort: 80
        env:
        - name: FTLCONF_dns_listeningMode
          value: ALL
        - name: FTLCONF_dns_upstreams
          value: 8.8.8.8;8.8.4.4
        - name: FTLCONF_dns_rateLimit_count
          value: '0'
        - name: FTLCONF_misc_dnsmasq_lines
          value: local-ttl=60;address=/${BASE_DOMAIN}/${GATEWAY_VIP};address=/unifi.${BASE_DOMAIN}/${UNIFI_L4_VIP};address=/crafty-mc.${BASE_DOMAIN}/${CRAFTY_L4_VIP};address=/pihole-dns.${BASE_DOMAIN}/${PIHOLE_DNS_VIP};address=/plex-vip.${BASE_DOMAIN}/${PLEX_L4_VIP}
        - name: FTLCONF_webserver_api_password
          valueFrom:
            secretKeyRef:
              name: pihole-bootstrap
              key: webui-password
        volumeMounts:
        - name: config
          mountPath: /etc/pihole
        lifecycle:
          postStart:
            exec:
              command:
              - /bin/bash
              - -c
              - "# Assert the declared adlists in gravity.db. Idempotent: steady state writes nothing and\n# does NOT run a gravity rebuild.\nset -u\nGRAVITY=/etc/pihole/gravity.db\n\n# THE DECLARED SET \u2014 one URL per line, the source of truth for what PiHole blocks.\n# To add a list: add a line here, commit, let Flux reconcile. Nothing else to do.\nDECLARED='https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts'\n\n# On a fresh PVC, FTL creates gravity.db a moment after the container starts. Wait, bounded,\n# and NEVER block or fail the start: a missing DB here must not crashloop DNS for the LAN.\ni=0\nwhile [ ! -s \"$GRAVITY\" ] && [ \"$i\" -lt 90 ]; do sleep 2; i=$(expr $i + 1); done\nif [ ! -s \"$GRAVITY\" ]; then\n  echo \"pihole-adlists: gravity.db absent after 180s - leaving adlists untouched\" >&2\n  exit 0\nfi\n\nsql() { pihole-FTL sqlite3 \"$GRAVITY\" \"$1\"; }\nCHANGED=0\n\n# 1) Every declared URL must be present AND enabled.\necho \"$DECLARED\" | while IFS= read -r url; do\n  [ -n \"$url\" ] || continue\n  printf '%s\\n' \"$url\"\ndone > /tmp/declared.txt\nwhile IFS= read -r url; do\n  [ -n \"$url\" ] || continue\n  # Single quotes inside a URL would break this SQL; adlist URLs do not contain them.\n  have=$(sql \"select count(*) from adlist where address='$url';\")\n  if [ \"$have\" = \"0\" ]; then\n    echo \"pihole-adlists: adding $url\"\n    sql \"insert into adlist (address,enabled,comment) values ('$url',1,'declared in catalog/pihole.yaml');\"\n    CHANGED=1\n  else\n    en=$(sql \"select enabled from adlist where address='$url';\")\n    if [ \"$en\" != \"1\" ]; then\n      echo \"pihole-adlists: re-enabling $url\"\n      sql \"update adlist set enabled=1 where address='$url';\"\n      CHANGED=1\n    fi\n  fi\ndone < /tmp/declared.txt\n\n# 2) Anything enabled in the DB but NOT declared gets disabled (never deleted - see above).\nsql \"select address from adlist where enabled=1;\" | while IFS= read -r addr; do\n  [ -n \"$addr\" ] || continue\n  if ! grep -qxF \"$addr\" /tmp/declared.txt; then\n    echo \"pihole-adlists: disabling undeclared $addr\"\n    sql \"update adlist set enabled=0 where address='$addr';\"\n    echo changed >> /tmp/adlist-changed\n  fi\ndone\n[ -s /tmp/adlist-changed ] && CHANGED=1\nrm -f /tmp/adlist-changed /tmp/declared.txt\n\n# 3) Rebuild gravity ONLY if the declared set actually moved.\nif [ \"$CHANGED\" = \"1\" ]; then\n  echo \"pihole-adlists: declared set changed - running gravity update\"\n  pihole -g || echo \"pihole-adlists: gravity update failed; existing gravity.db retained\" >&2\nelse\n  echo \"pihole-adlists: already matches the declared set - nothing to do\"\nfi\nexit 0\n"
      - name: oauth2-proxy
        image: quay.io/oauth2-proxy/oauth2-proxy:v7.8.1
        imagePullPolicy: IfNotPresent
        args:
        - --http-address=0.0.0.0:4180
        - --reverse-proxy=true
        - --provider=oidc
        - --oidc-issuer-url=https://keycloak.${BASE_DOMAIN}/realms/homelab
        - --upstream=http://127.0.0.1:80
        - --email-domain=*
        - --scope=openid email profile
        - --oidc-groups-claim=groups
        - --allowed-group=platform-admins
        - --skip-provider-button=true
        - --redirect-url=https://pihole.${BASE_DOMAIN}/oauth2/callback
        - --cookie-name=_oauth2_proxy_pihole
        - --cookie-domain=pihole.${BASE_DOMAIN}
        - --whitelist-domain=.${BASE_DOMAIN}
        - --cookie-secure=true
        - --cookie-refresh=2m30s
        - --pass-access-token=true
        - --set-xauthrequest=true
        - --metrics-address=0.0.0.0:44180
        env:
        - name: OAUTH2_PROXY_CLIENT_ID
          valueFrom:
            secretKeyRef:
              name: pihole-oauth2-proxy
              key: client-id
        - name: OAUTH2_PROXY_CLIENT_SECRET
          valueFrom:
            secretKeyRef:
              name: pihole-oauth2-proxy
              key: client-secret
        - name: OAUTH2_PROXY_COOKIE_SECRET
          valueFrom:
            secretKeyRef:
              name: pihole-oauth2-proxy
              key: cookie-secret
        ports:
        - name: http
          containerPort: 4180
          protocol: TCP
        - name: metrics
          containerPort: 44180
          protocol: TCP
        resources:
          requests:
            cpu: 25m
            memory: 64Mi
          limits:
            memory: 128Mi
        securityContext:
          allowPrivilegeEscalation: false
          readOnlyRootFilesystem: true
          capabilities:
            drop:
            - ALL
        livenessProbe:
          httpGet:
            path: /ping
            port: http
          initialDelaySeconds: 5
          periodSeconds: 15
        readinessProbe:
          httpGet:
            path: /ping
            port: http
          initialDelaySeconds: 5
          periodSeconds: 15
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchLabels:
                app.kubernetes.io/name: pihole
            topologyKey: kubernetes.io/hostname
  volumeClaimTemplates:
  - metadata:
      name: config
      labels:
        app.kubernetes.io/name: pihole
    spec:
      accessModes:
      - ReadWriteOnce
      storageClassName: longhorn
      resources:
        requests:
          storage: 2Gi
---
# PodDisruptionBudget — keep one replica through a drain (availability.replicas)
apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: pihole
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  minAvailable: 1
  selector:
    matchLabels:
      app.kubernetes.io/name: pihole
---
# Service
apiVersion: v1
kind: Service
metadata:
  name: pihole
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  selector:
    app.kubernetes.io/name: pihole
  ports:
  - name: port-80
    port: 80
    targetPort: 80
  - name: authproxy
    port: 4180
    targetPort: 4180
---
# CiliumNetworkPolicy gateway-ingress allow (R-NET-01/02): pihole-allow-gateway-ingress
apiVersion: cilium.io/v2
kind: CiliumNetworkPolicy
metadata:
  name: pihole-allow-gateway-ingress
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  endpointSelector:
    matchLabels:
      app.kubernetes.io/name: pihole
  ingress:
  - fromEntities:
    - ingress
    toPorts:
    - ports:
      - port: '4180'
        protocol: TCP
---
# CiliumNetworkPolicy monitoring scrape ingress allow (R-NET-02/R-OBS-01): pihole-allow-monitoring-scrape
apiVersion: cilium.io/v2
kind: CiliumNetworkPolicy
metadata:
  name: pihole-allow-monitoring-scrape
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  endpointSelector:
    matchLabels:
      app.kubernetes.io/name: pihole
  ingress:
  - fromEndpoints:
    - matchLabels:
        k8s:io.kubernetes.pod.namespace: monitoring
    toPorts:
    - ports:
      - port: '44180'
        protocol: TCP
---
# CiliumNetworkPolicy world egress allow (egress class governs the path; R-NET-05): pihole-allow-internet-egress
apiVersion: cilium.io/v2
kind: CiliumNetworkPolicy
metadata:
  name: pihole-allow-internet-egress
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
spec:
  endpointSelector:
    matchLabels:
      app.kubernetes.io/name: pihole
  egress:
  - toEntities:
    - world
  - toEndpoints:
    - matchLabels:
        io.kubernetes.pod.namespace: keycloak
        app: keycloak
---
# HTTPRoute pihole-80 (R-TLS/R-DNS)
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: pihole-80
  namespace: pihole
  labels:
    app.kubernetes.io/name: pihole
  annotations:
    homelab.keithjackson.dev/auth-mode: forward-auth
    homelab.keithjackson.dev/auth-groups: platform-admins
    external-dns.alpha.kubernetes.io/controller: none
spec:
  parentRefs:
  - name: shared
    namespace: gateway
    sectionName: https
  hostnames:
  - pihole.${BASE_DOMAIN}
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: pihole
      port: 4180
---
# PrometheusRule SLI alerts (R-OBS-01)
apiVersion: monitoring.coreos.com/v1
kind: PrometheusRule
metadata:
  name: pihole-slis
  namespace: pihole
  labels:
    release: kube-prometheus-stack
    app.kubernetes.io/name: pihole
spec:
  groups:
  - name: pihole.slis
    rules:
    - alert: pihole-down
      expr: kube_statefulset_status_replicas_ready{namespace="pihole", statefulset="pihole"} == 0 or absent(kube_statefulset_status_replicas_ready{namespace="pihole", statefulset="pihole"})
      for: 5m
      labels:
        severity: critical
        service: pihole
      annotations:
        summary: pihole is down
        description: 'pihole: its StatefulSet has no available/ready replica for 5m, or the signal is gone entirely (SLI: up, via kube_statefulset_status_replicas_ready).'