fix(backups): Repair three broken CronJobs blocking weekly OS updates (DEV-464)

- Create the missing forgejo/platform-backup-data PVC that forgejo-backup
  references (20Gi hcloud-volumes-encrypted).
- Record monitoring/backup-k8s-resources with a k3s-worker-2 nodeSelector
  (backup-storage PVC is local-path pinned there), lower memory request
  (128Mi) so it fits worker-2 pressure, and switch to alpine/k8s image
  (bitnami/kubectl is no longer resolvable).
- Rewrite monitoring/backup-volumes to only back up grafana + loki
  co-located with backup-storage on k3s-worker-2. Prometheus data
  lives on k3s-worker-1 and is intentionally excluded here; a
  dedicated Prometheus data backup follows in a separate ticket.

The three CronJobs previously left Pending/ContainerCreating pods that
blocked the OS-update health guard in DEV-463.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/forgejo/platform-backup-data-pvc.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: platform-backup-data
+  namespace: forgejo
+  labels:
+    app: forgejo-backup
+spec:
+  accessModes:
+  - ReadWriteOnce
+  storageClassName: hcloud-volumes-encrypted
+  resources:
+    requests:
+      storage: 20Gi

apps/monitoring/README.md

@@ -0,0 +1,10 @@
+# monitoring — backup CronJobs
+
+Manifests recording the cluster-side monitoring backup CronJobs that were previously applied out-of-band. These files are the authoritative source (`kubectl apply -f apps/monitoring/`). See [DEV-464](/DEV/issues/DEV-464) for the repair context.
+
+- `backup-k8s-resources-cronjob.yaml` — daily dump of Kubernetes resources into `backup-storage` PVC.
+- `backup-volumes-cronjob.yaml` — daily rsync/tar of Grafana + Loki PVCs into `backup-storage`. Prometheus data backup is **not** included here; it needs a separate on-node backup (tracked as a follow-up because Prometheus is on a different node than `backup-storage`).
+
+The `backup-storage` PVC (100Gi, local-path, bound to k3s-worker-2) is the shared destination for both jobs.
+
+Both CronJobs pin themselves to `k3s-worker-2` via `nodeSelector` because that is the node that holds all destination + source PVCs used here.

apps/monitoring/backup-k8s-resources-cronjob.yaml

@@ -0,0 +1,84 @@
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: backup-k8s-resources
+  namespace: monitoring
+  labels:
+    app: backup
+    type: k8s-resources
+spec:
+  schedule: "0 2 * * *"
+  concurrencyPolicy: Forbid
+  successfulJobsHistoryLimit: 3
+  failedJobsHistoryLimit: 3
+  jobTemplate:
+    metadata:
+      annotations:
+        prometheus.io/scrape: "true"
+      labels:
+        app: backup
+        type: k8s-resources
+    spec:
+      backoffLimit: 2
+      template:
+        metadata:
+          labels:
+            app: backup
+        spec:
+          restartPolicy: OnFailure
+          serviceAccountName: backup-sa
+          # backup-storage PVC (local-path) is bound to k3s-worker-2, so pin here.
+          nodeSelector:
+            kubernetes.io/hostname: k3s-worker-2
+          containers:
+          - name: kubectl-backup
+            image: alpine/k8s:1.29.4
+            command:
+            - /bin/sh
+            - -c
+            - |
+              set -e
+              BACKUP_DIR="/backup/k8s-$(date +%Y%m%d-%H%M%S)"
+              mkdir -p "$BACKUP_DIR"
+
+              echo "Starting Kubernetes resources backup to $BACKUP_DIR"
+
+              kubectl get namespaces -o yaml > "$BACKUP_DIR/namespaces.yaml"
+
+              for ns in $(kubectl get namespaces -o jsonpath='{.items[*].metadata.name}'); do
+                mkdir -p "$BACKUP_DIR/$ns"
+                kubectl get configmaps,secrets,services,deployments,statefulsets,daemonsets,jobs,cronjobs,ingresses,persistentvolumeclaims \
+                  -n "$ns" -o yaml > "$BACKUP_DIR/$ns/resources.yaml" 2>/dev/null || true
+              done
+
+              kubectl get persistentvolumes,storageclasses,clusterroles,clusterrolebindings \
+                -o yaml > "$BACKUP_DIR/cluster-resources.yaml"
+
+              cd /backup
+              tar -czf "k8s-backup-$(date +%Y%m%d-%H%M%S).tar.gz" "$(basename $BACKUP_DIR)"
+              rm -rf "$BACKUP_DIR"
+
+              find /backup -name "k8s-backup-*.tar.gz" -mtime +7 -delete
+
+              echo "Backup completed successfully"
+
+              echo "backup_k8s_resources_success 1" > /metrics/backup_success.prom
+              echo "backup_k8s_resources_timestamp $(date +%s)" >> /metrics/backup_success.prom
+            resources:
+              requests:
+                cpu: 50m
+                memory: 128Mi
+              limits:
+                cpu: 500m
+                memory: 384Mi
+            volumeMounts:
+            - mountPath: /backup
+              name: backup-storage
+            - mountPath: /metrics
+              name: metrics
+          volumes:
+          - name: backup-storage
+            persistentVolumeClaim:
+              claimName: backup-storage
+          - name: metrics
+            emptyDir: {}

apps/monitoring/backup-volumes-cronjob.yaml

@@ -0,0 +1,102 @@
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: backup-volumes
+  namespace: monitoring
+  labels:
+    app: backup
+    type: volumes
+spec:
+  schedule: "0 3 * * *"
+  concurrencyPolicy: Forbid
+  successfulJobsHistoryLimit: 3
+  failedJobsHistoryLimit: 3
+  jobTemplate:
+    metadata:
+      annotations:
+        prometheus.io/scrape: "true"
+      labels:
+        app: backup
+        type: volumes
+    spec:
+      backoffLimit: 2
+      template:
+        metadata:
+          labels:
+            app: backup
+        spec:
+          restartPolicy: OnFailure
+          # backup-storage, grafana-storage and loki-storage-encrypted are all
+          # RWO PVCs pinned to k3s-worker-2. Prometheus data lives on
+          # k3s-worker-1 and is intentionally NOT backed up here — see
+          # DEV-464 for the split rationale and the follow-up ticket for
+          # a dedicated Prometheus data backup.
+          nodeSelector:
+            kubernetes.io/hostname: k3s-worker-2
+          containers:
+          - name: volume-backup
+            image: alpine:3.19
+            command:
+            - /bin/sh
+            - -c
+            - |
+              set -e
+              apk add --no-cache rsync
+
+              BACKUP_DATE=$(date +%Y%m%d-%H%M%S)
+              BACKUP_DIR="/backup/volumes-$BACKUP_DATE"
+              mkdir -p "$BACKUP_DIR"
+
+              echo "Starting volume backup to $BACKUP_DIR"
+
+              if [ -d "/source/grafana" ]; then
+                echo "Backing up Grafana data..."
+                rsync -a /source/grafana/ "$BACKUP_DIR/grafana/" || echo "Warning: Grafana backup incomplete"
+              fi
+
+              if [ -d "/source/loki" ]; then
+                echo "Backing up Loki data..."
+                rsync -a /source/loki/ "$BACKUP_DIR/loki/" || echo "Warning: Loki backup incomplete"
+              fi
+
+              cd /backup
+              tar -czf "volumes-backup-$BACKUP_DATE.tar.gz" "$(basename $BACKUP_DIR)"
+              rm -rf "$BACKUP_DIR"
+
+              find /backup -name "volumes-backup-*.tar.gz" -mtime +7 -delete
+
+              BACKUP_SIZE=$(du -sh "/backup/volumes-backup-$BACKUP_DATE.tar.gz" | cut -f1)
+              echo "Volume backup completed successfully: $BACKUP_SIZE"
+
+              echo "backup_volumes_success 1" > /metrics/backup_success.prom
+              echo "backup_volumes_timestamp $(date +%s)" >> /metrics/backup_success.prom
+            resources:
+              requests:
+                cpu: 100m
+                memory: 128Mi
+              limits:
+                cpu: 1000m
+                memory: 512Mi
+            volumeMounts:
+            - mountPath: /backup
+              name: backup-storage
+            - mountPath: /source/grafana
+              name: grafana-data
+              readOnly: true
+            - mountPath: /source/loki
+              name: loki-data
+              readOnly: true
+            - mountPath: /metrics
+              name: metrics
+          volumes:
+          - name: backup-storage
+            persistentVolumeClaim:
+              claimName: backup-storage
+          - name: grafana-data
+            persistentVolumeClaim:
+              claimName: grafana-storage
+          - name: loki-data
+            persistentVolumeClaim:
+              claimName: loki-storage-encrypted
+          - name: metrics
+            emptyDir: {}