Creating a VolumeReplication

Create a VolumeReplication YAML file to replicate a specific PersistentVolumeClaim (PVC).

VolumeReplicationClass needs to be present before a VolumeReplication can be created. For more information, see Creating a VolumeReplicationClass.

Remote copy function is referred to as the more generic volume replication within this documentation set. Not all supported products use the remote-copy function terminology.

When replicating a volume, be sure to follow all of the replication configurations, found in Compatibility and requirements before volume replication.

• When policy-based replication is not being used, use the spec.csi.volumeHandle of the relevant target PersistentVolume (PV) for the replicationHandle value.
• When policy-based replication is being used, do not use the replicationHandle value. Using the replicationHandle while policy-based replication is defined in the VolumeReplicationClass results in the following error message: got an invalid parameter: replicationHandle.
• spec.dataSource.kind values are PersistentVolumeClaim or VolumeGroup. Only one value can be used at a time. Only use the VolumeGroup value when policy-based replication is being used.
• spec.dataSource.name value must be the VolumeGroup name, when policy-based replication is being used.

1. Replicate a specific PersistentVolumeClaim (PVC) using the demo-volumereplication.yaml.

   For more information about PVC configuration, see Creating a PersistentVolumeClaim (PVC).

   apiVersion: replication.storage.openshift.io/v1alpha1
   kind: VolumeReplication
   metadata:
     name: demo-volumereplication
     namespace: default
   spec:
     volumeReplicationClass: demo-volumereplicationclass
     replicationState: primary
     replicationHandle: demo-volumehandle
     dataSource:
       kind: PersistentVolumeClaim
       name: demo-pvc-file-system  # Ensure that this is in the same namespace as VolumeReplication.
   

2. After the YAML file is created, apply it by using the kubectl apply -f command.

   kubectl apply -f <filename>.yaml
   

   The volumereplication.replication.storage.openshift.io/<volumereplication-name> created message is emitted.

3. Verify that the volume was replicated.

   Run the kubectl describe volumereplication command.

   See the status.state section to see which of the following states the replication is in:

   • Primary Indicates that the source volume is the primary volume.
   • Secondary Indicates that the source volume is the secondary volume.
   • Unknown Indicates that the driver does not recognize the replication state.

For information about changing the replication state, see the Usage section of the Volume Replication Operator for csi-addons.