The CrashLoopBackOff pod using local persistentVolume in cloud cluster

2/17/2020

I tried to create a postgres pod with local persistentVolume.

kind: PersistentVolume
apiVersion: v1
metadata:
  name: pv-postgres
spec:
  capacity:
    storage: 1Gi
  volumeMode: Filesystem
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /postgres
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: node-role.kubernetes.io/work
          operator: In
          values:
          - work1
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: pvc-postgres
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
  storageClassName: local-storage
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: postgres
spec:
  selector:
    matchLabels:
      app: postgres
  replicas: 1
  strategy: {}
  template:
    metadata:
      labels:
        app: postgres
    spec:
      nodeSelector:
        node-role.kubernetes.io/work: work1
      dnsPolicy: ClusterFirstWithHostNet
      hostNetwork: true
      volumes:
      - name: vol-postgres
        persistentVolumeClaim:
          claimName: pvc-postgres
      containers:
      - name: postgres
        image: postgres:12
        imagePullPolicy: Always
        env:
        - name: DB_USER
          value: postgres
        - name: DB_PASS
          value: postgres
        - name: DB_NAME
          value: postgres
        ports:
        - name: postgres
          containerPort: 5432
        volumeMounts:
        - mountPath: /postgres
          name: vol-postgres
        livenessProbe:
          exec:
            command:
            - pg_isready
            - -h
            - localhost
            - -U
            - postgres
          initialDelaySeconds: 30
          timeoutSeconds: 5
        readinessProbe:
          exec:
            command:
            - pg_isready
            - -h
            - localhost
            - -U
            - postgres
          initialDelaySeconds: 5
          timeoutSeconds: 1
---
apiVersion: v1
kind: Service
metadata:
  name: postgres
spec:
  ports:
  - name: postgres
    port: 5432
    targetPort: postgres
  selector:
    app: postgres

But the pod status is always CrashLoopBackOff without any other error message when I using kubectl describe pod.

The deployment and service can be running isolation, the error happened when I add pv and pvc to this yaml file. It seems the persistentVolume not be correctly assigned, how should I fix it?

-- ccd
kubernetes

1 Answer

2/17/2020

Because of the local type of persistentVolume, it is recommended to add the StorageClass to yaml file.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer
-- ccd
Source: StackOverflow