4.9. Persistent storage using NFS

Procedure

1. Create an object definition for the PV:

   apiVersion: v1
   kind: PersistentVolume
   metadata:
     name: pv0001 

   1

   
   spec:
     capacity:
       storage: 5Gi 

   2

   
     accessModes:
     - ReadWriteOnce 

   3

   
     nfs: 

   4

   
       path: /tmp 

   5

   
       server: 172.17.0.2 

   6

   
     persistentVolumeReclaimPolicy: Retain 

   7

   1

   The name of the volume. This is the PV identity in various oc <command> pod commands.

   2

   The amount of storage allocated to this volume.

   3

   Though this appears to be related to controlling access to the volume, it is actually used similarly to labels and used to match a PVC to a PV. Currently, no access rules are enforced based on the accessModes.

   4

   The volume type being used, in this case the nfs plugin.

   5

   The path that is exported by the NFS server.

   6

   The hostname or IP address of the NFS server.

   7

   The reclaim policy for the PV. This defines what happens to a volume when released.

   注意

   Each NFS volume must be mountable by all schedulable nodes in the cluster.

2. Verify that the PV was created:

   $ oc get pv

   Example output

   NAME     LABELS    CAPACITY     ACCESSMODES   STATUS      CLAIM  REASON    AGE
   pv0001   <none>    5Gi          RWO           Available                    31s

3. Create a persistent volume claim that binds to the new PV:

   apiVersion: v1
   kind: PersistentVolumeClaim
   metadata:
     name: nfs-claim1
   spec:
     accessModes:
       - ReadWriteOnce 

   1

   
     resources:
       requests:
         storage: 5Gi 

   2

   
     volumeName: pv0001
     storageClassName: ""

   1

   The access modes do not enforce security, but rather act as labels to match a PV to a PVC.

   2

   This claim looks for PVs offering 5Gi or greater capacity.

4. Verify that the persistent volume claim was created:

   $ oc get pvc

   Example output

   NAME         STATUS   VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS   AGE
   nfs-claim1   Bound    pv0001   5Gi        RWO                           2m