State Persistence

PersistentVolumeClaim

Create PersistentVolumeClaim named "xpvc" with access mode ReadWriteOnce and resources 2 GB:

nano pvc.yaml 

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: xpvc
spec:
  storageClassName: normal
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

kubectl apply -f pvc.yaml

PersistentVolume

Create busybox that run a command 'cp /etc/passwd /etc/xvolume/' pod. Map "/etc/xvolume" in the pod to persistent volume using the previous PersistentVolumeClaim "xpvc":

kubectl run busybox1 --image=busybox --restart=Never -o yaml --dry-run -- /bin/sh -c 'cp /etc/passwd /etc/xvolume/'  > pod1.yam
kubectl apply -f pod1.yaml

# Edit pod.yaml and add volumes and volumeMounts
...
spec:
  volumes:
    - name: xpv
      persistentVolumeClaim:
        claimName: xpvc
...

# volumeMounts for the container
...
  volumeMounts:
  - mountPath: "/etc/xvolume"
    name: xpv
...

Create the same as the previous pod with same configuration but override the command to 'cat /etc/xvolume/passwd':

kubectl run busybox2 --image=busybox --restart=Never -o yaml --dry-run -- /bin/sh -c 'cat /etc/xvolume/passwd'  > pod2.yaml
kubectl apply -f pod2.yaml
kubectl logs busybox2