Adding volume expansion support for replicated (#305)

content/docs/csidriver/features/powermax.md

@@ -160,8 +160,6 @@ To install multiple CSI drivers, follow these steps:
 
 Starting in v1.4, the CSI PowerMax driver supports the expansion of Persistent Volumes (PVs). This expansion is done online, which is when the PVC is attached to any node.
 
->Note: This feature is not supported for replicated volumes.
-
 To use this feature, enable in `values.yaml`
 
 ```yaml
@@ -564,4 +562,4 @@ spec:
 
 When this feature is enabled, the existing `ReadWriteOnce(RWO)` access mode restricts volume access to a single node and allows multiple pods on the same node to read from and write to the same volume.
 
-To migrate existing PersistentVolumes to use `ReadWriteOncePod`, please follow the instruction from [here](https://kubernetes.io/blog/2021/09/13/read-write-once-pod-access-mode-alpha/#migrating-existing-persistentvolumes).
+To migrate existing PersistentVolumes to use `ReadWriteOncePod`, please follow the instruction from [here](https://kubernetes.io/blog/2021/09/13/read-write-once-pod-access-mode-alpha/#migrating-existing-persistentvolumes).

content/docs/csidriver/release/powermax.md

@@ -6,16 +6,7 @@ description: Release notes for PowerMax CSI driver
 ## Release Notes - CSI PowerMax v2.3.0
 
 ### New Features/Changes
-- Updated deprecated StorageClass parameter fsType with csi.storage.k8s.io/fstype.
-- Added support for Standalone Helm Charts.
-- Removed beta volumesnapshotclass sample files.
-- Added mapping of PV/PVC to namespace.
-- Added support to configure fsGroupPolicy.
-- Added support to filter topology keys based on user inputs.
-- Added support for SRDF Metro group sharing multiple namespaces.
-- Added support for Kubernetes 1.24.
-- Added support for OpenShift 4.10.
-- Added support to convert replicated volume to non-replicated volume and vice versa for Sync and Async modes.
+- Online volume expansion for replicated volumes.
 
 ### Fixed Issues
 There are no fixed issues in this release.

content/docs/replication/_index.md

@@ -22,6 +22,7 @@ CSM for Replication provides the following capabilities:
 | Create `PersistentVolume` objects in the cluster representing the replicated volume | yes      | yes        | yes        | no        | no    |
 | Create `DellCSIReplicationGroup` objects in the cluster                             | yes      | yes        | yes        | no        | no    |
 | Failover & Reprotect applications using the replicated volumes                      | yes      | yes        | yes        | no        | no    |
+| Online Volume Expansion for replicated volumes				       | yes      | no	      | no	   | no	       | no    |
 | Provides a command line utility - [repctl](tools) for configuring & managing replication related resources across multiple clusters | yes | yes | yes | no | no |
 {{</table>}}
 

content/docs/replication/volume_expansion.md

@@ -0,0 +1,44 @@
+---
+title: Volume Expansion
+linktitle: Volume Expansion
+weight: 6
+description: >
+  Online expansion of replicated volumes
+---
+
+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.
+```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.
+
+```yaml
+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.