Chapter 3. Expanding persistent volumes

Procedure

1. Edit the PVC and request a new size by editing spec.resources.requests. For example, the following expands the ebs PVC to 8 Gi.

   kind: PersistentVolumeClaim
   apiVersion: v1
   metadata:
     name: ebs
   spec:
     storageClass: "storageClassWithFlagSet"
     accessModes:
       - ReadWriteOnce
     resources:
       requests:
         storage: 8Gi 1

   1

   Updating spec.resources.requests to a larger amount will expand the PVC.

2. Once the cloud provider object has finished resizing, the PVC is set to FileSystemResizePending. The following command is used to check the condition:

   $ oc describe pvc <pvc_name>

3. When the cloud provider object has finished resizing, the persistent volume object reflects the newly requested size in PersistentVolume.Spec.Capacity. At this point, you can create or recreate a new pod from the PVC to finish the file system resizing. Once the pod is running, the newly requested size is available and the FileSystemResizePending condition is removed from the PVC.

Procedure

1. Mark the persistent volume (PV) that is bound to the PVC with the Retain reclaim policy. This can be done by editing the PV and changing persistentVolumeReclaimPolicy to Retain.
2. Delete the PVC. This will be recreated later.
3. To ensure that the newly created PVC can bind to the PV marked Retain, manually edit the PV and delete the claimRef entry from the PV specs. This marks the PV as Available.
4. Re-create the PVC in a smaller size, or a size that can be allocated by the underlying storage provider.
5. Set the volumeName field of the PVC to the name of the PV. This binds the PVC to the provisioned PV only.
6. Restore the reclaim policy on the PV.