My Kubernetes StorageClass volume doesn't retain existing data when the pod is deleted and deployed back with my postgresql database. When I delete the pod, the new pod is created but the database is empty.

I have followed variations of the different versions of the tutorials (https://kubernetes.io/docs/concepts/storage/persistent-volumes/) but nothing seems to work.

I paste all the YAML files cause the problem might be in the combination.

storage-google.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: spingular-pvc
spec:
  storageClassName: standard
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 7Gi
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: standard
provisioner: kubernetes.io/gce-pd
parameters:
  type: pd-standard
  zone: us-east4-a

jhipsterpress-postgresql.yml

apiVersion: v1
kind: Secret
metadata:
  name: jhipsterpress-postgresql
  namespace: default
  labels:
    app: jhipsterpress-postgresql
type: Opaque
data:
  postgres-password: NjY0NXJxd24=
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: jhipsterpress-postgresql
  namespace: default
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: jhipsterpress-postgresql
    spec:
      volumes:
      - name: data
        persistentVolumeClaim:
          claimName: spingular-pvc
      containers:
      - name: postgres
        image: postgres:10.4
        env:
        - name: POSTGRES_USER
          value: jhipsterpress
        - name: POSTGRES_PASSWORD
          valueFrom:
            secretKeyRef:
              name: jhipsterpress-postgresql
              key: postgres-password
        ports:
        - containerPort: 5432
        volumeMounts:
        - name: data
          mountPath: /var/lib/postgresql/
---
apiVersion: v1
kind: Service
metadata:
  name: jhipsterpress-postgresql
  namespace: default
spec:
  selector:
    app: jhipsterpress-postgresql
  ports:
  - name: postgresqlport
    port: 5432
  type: LoadBalancer

jhipsterpress-deployment.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: jhipsterpress
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: jhipsterpress
      version: "v1"
  template:
    metadata:
      labels:
        app: jhipsterpress
        version: "v1"
    spec:
      initContainers:
        - name: init-ds
          image: busybox:latest
          command:
            - '/bin/sh'
            - '-c'
            - |
                while true
                do
                  rt=$(nc -z -w 1 jhipsterpress-postgresql 5432)
                  if [ $? -eq 0 ]; then
                    echo "DB is UP"
                    break
                  fi
                  echo "DB is not yet reachable;sleep for 10s before retry"
                  sleep 10
                done
      containers:
      - name: jhipsterpress-app
        image: galore/jhipsterpress
        env:
        - name: SPRING_PROFILES_ACTIVE
          value: prod
        - name: SPRING_DATASOURCE_URL
          value: jdbc:postgresql://jhipsterpress-postgresql.default.svc.cluster.local:5432/jhipsterpress
        - name: SPRING_DATASOURCE_USERNAME
          value: jhipsterpress
        - name: SPRING_DATASOURCE_PASSWORD
          valueFrom:
            secretKeyRef:
              name: jhipsterpress-postgresql
              key: postgres-password
        - name: JAVA_OPTS
          value: " -Xmx256m -Xms256m"
        resources:
          requests:
            memory: "256Mi"
            cpu: "500m"
          limits:
            memory: "512Mi"
            cpu: "1"
        ports:
        - name: http
          containerPort: 8080
        readinessProbe:
          httpGet:
            path: /management/health
            port: http
          initialDelaySeconds: 20
          periodSeconds: 15
          failureThreshold: 6
        livenessProbe:
          httpGet:
            path: /management/health
            port: http
          initialDelaySeconds: 120

jhipsterpress-service.yml

apiVersion: v1
kind: Service
metadata:
  name: jhipsterpress
  namespace: default
  labels:
    app: jhipsterpress
spec:
  selector:
    app: jhipsterpress
  type: LoadBalancer
  ports:
  - name: http
    port: 8080

When I included a Retain Policy I was getting this error:

@cloudshell:~ (academic-veld-230622)$ kubectl apply -f storage-google.yaml
error: error validating "storage-google.yaml": error validating data: 
ValidationError(PersistentVolumeClaim.spec): unknown field "persistentVolumeReclaimPolicy" in io.k8s.api.core.v1.PersistentVolumeClaimSpec; if you choose to ignore these errors, turn validation off with --validate=false

Please, if you know of a complete example on a public image that works (in postgresql, I can make it work with Mongo), I will really appreciate it.

Thanks to all.