Volume Expansion

Starting in v2.4.0, the CSI PowerMax driver supports the expansion of Replicated Persistent Volumes (PVs). This expansion is done online, which is when the PVC is attached to any node.

Prerequisites

• To use this feature, enable resizer in values.yaml:

resizer:
  enabled: true

• To use this feature, the storage class that is used to create the PVC must have the attribute allowVolumeExpansion set to true.

Basic Usage

To resize a PVC, edit the existing PVC spec and set spec.resources.requests.storage to the intended size. For example, if you have a PVC pmax-pvc-demo of size 5 Gi, then you can resize it to 10 Gi by updating the PVC:

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: pmax-pvc-demo
  namespace: test
spec:
  accessModes:
  - ReadWriteOnce
  volumeMode: Filesystem
  resources:
    requests:
      storage: 10Gi #Updated size from 5Gi to 10Gi
  storageClassName: powermax-expand-sc

Update remote PVC with expanded size:

1. Update the remote PVC size with the same size as on local PVC.

2. After sync with remote CSI driver, volume size will be updated to show new size.

NOTE: The Kubernetes Volume Expansion feature can only be used to increase the size of the volume, it cannot be used to shrink a volume.