Implement State Persistence for Kubernetes Pods

Create a descriptor file with vi mysql-pv.yml:

kind: PersistentVolume
apiVersion: v1
metadata:
  name: mysql-pv
spec:
  storageClassName: localdisk
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data"

Create the PersistentVolume.

kubectl apply -f mysql-pv.yml

Create a descriptor file with vi mysql-pv-claim.yml:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pv-claim
spec:
  storageClassName: localdisk
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 500Mi

Create the PersistentVolumeClaim:

kubectl apply -f mysql-pv-claim.yml

Create a descriptor file with vi mysql-pod.yml:

apiVersion: v1
kind: Pod
metadata:
  name: mysql-pod
spec:
  containers:
  - name: mysql
    image: mysql:5.6
    ports:
    - containerPort: 3306
    env:
    - name: MYSQL_ROOT_PASSWORD
      value: password
    volumeMounts:
    - name: mysql-storage
      mountPath: /var/lib/mysql
  volumes:
  - name: mysql-storage
    persistentVolumeClaim:
      claimName: mysql-pv-claim

Create the Pod:

kubectl apply -f mysql-pod.yml

Check the status of the pod with kubectl get pod mysql-pod. After a few moments it should be in the RUNNING status.

You can also verify that the pod is interacting with the filesystem at /mnt/data on the node. Log in to the node from the Kube master like this, using the same as the password for the kube master:

ssh [email protected]

Check the contents of the PersistentVolume directory:

ls /mnt/data

You should see files and directories there related to MySQL. These were created by the pod, meaning that your PersistentVolume and PersistentVolumeClaim are working!