Kubernetes Nexcloud Postgres: SQLSTATE[08006] [7] could not translate host name to address: Temporary failure in name resolution

Question

Issue

Hello, I want to set up a Nextcloud w/ Postgres as a database instance on my Kubernetes cluster. However, when I define the env variables for Postgres in the Nextcloud deployment file, the Nextcloud pod instance can't connect to the Postgres pod instance based on the service name. If anyone can give me any suggestions on what to do to solve this, please. Thank you in advance.

Error

Here is the result of kubectl logs <pod-name> command for the Nexcloud pod instance:

Previous: Doctrine\DBAL\Exception: Failed to connect to the database: An exception occurred in the driver: SQLSTATE[08006] [7] could not translate host name "home-drive-db" to address: Temporary failure in name resolution
Trace: #0 /var/www/html/lib/private/Setup/PostgreSQL.php(98): OC\DB\Connection->connect()
#1 /var/www/html/lib/private/Setup.php(351): OC\Setup\PostgreSQL->setupDatabase('rafidini')
#2 /var/www/html/core/Command/Maintenance/Install.php(108): OC\Setup->install(Array)
#3 /var/www/html/3rdparty/symfony/console/Command/Command.php(255): OC\Core\Command\Maintenance\Install->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#4 /var/www/html/3rdparty/symfony/console/Application.php(1009): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#5 /var/www/html/3rdparty/symfony/console/Application.php(273): Symfony\Component\Console\Application->doRunCommand(Object(OC\Core\Command\Maintenance\Install), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#6 /var/www/html/3rdparty/symfony/console/Application.php(149): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#7 /var/www/html/lib/private/Console/Application.php(209): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#8 /var/www/html/console.php(99): OC\Console\Application->run()
#9 /var/www/html/occ(11): require_once('/var/www/html/c...')
#10 {main}
retrying install...

Files

home-drive-db.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: home-drive-app
  name: home-drive-db
spec:
  replicas: 1
  selector:
    matchLabels:
      pod-label: home-drive-db-pod
      app: home-drive-app
  template:
    metadata:
      labels:
        pod-label: home-drive-db-pod
        app: home-drive-app
    spec:
      containers:
        - name: home-drive-db
          image: postgres:alpine
          resources:
            limits:
              memory: 512Mi
              cpu: "1"
            requests:
              memory: 256Mi
              cpu: "0.2"
          ports:
            - containerPort: 5432
          env:
            - name: POSTGRES_DB
              value: nextcloud
            - name: POSTGRES_USER
              value: rafidini
            - name: POSTGRES_PASSWORD
              value: password1
          volumeMounts:
            - name: db-storage
              mountPath: /var/lib/postgresl/data
              subPath: postgres
      volumes:
        - name: db-storage
          persistentVolumeClaim:
            claimName: home-drive-shared-storage
---
apiVersion: v1
kind: Service
metadata:
  labels:
    app: home-drive-app
  name: home-drive-db
spec:
  type: ClusterIP
  selector:
    pod-label: home-drive-db-pod
    app: home-drive-app
  ports:
    - port: 5432
      protocol: TCP
      targetPort: 5432

home-drive-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    appe: home-drive-app
  name: home-drive-server
spec:
  replicas: 1
  selector:
    matchLabels:
      pod-label: home-drive-server-pod
      app: home-drive-app
  template:
    metadata:
      labels:
        pod-label: home-drive-server-pod
        app: home-drive-app
    spec:
      containers:
        - image: nextcloud:production
          ports:
            - containerPort: 5432
          env:
            - name: POSTGRES_HOST
              value: home-drive-db:5432
            - name: POSTGRES_DB
              value: nextcloud
            - name: POSTGRES_USER
              value: rafidini
            - name: POSTGRES_PASSWORD
              value: password1
            - name: NEXTCLOUD_ADMIN_USER
              value: rafidini
            - name: NEXTCLOUD_ADMIN_PASSWORD
              value: password1
          resources:
            limits:
              memory: 1Gi
              cpu: "1"
            requests:
              memory: 256Mi
              cpu: "1"
          name: home-drive-app
          volumeMounts:
            - name: server-storage
              mountPath: /var/www/html
              subPath: server-data
      volumes:
        - name: server-storage
          persistentVolumeClaim:
            claimName: home-drive-shared-storage
---
apiVersion: v1
kind: Service
metadata:
  labels:
    app: home-drive-app
  name: home-drive-server
spec:
  selector:
    app: home-drive-app
    pod-label: home-drive-server-pod
  ports:
    - protocol: TCP
      port: 80