Creating a VolumeSnapshotClass

Create a VolumeSnapshotClass YAML file to enable creation and deletion of volume snapshots.

This section refers to both the IBM FlashCopy® function and Snapshot function in IBM Storage Virtualize storage systems.

In order to enable creation and deletion of volume snapshots for your storage system, create a VolumeSnapshotClass YAML file, similar to the following demo-volumesnapshotclass.yaml.

When configuring the file, be sure to use the same array secret and array secret namespace as defined in Creating a Secret.

• The snapshot_name_prefix parameter is optional.

For IBM DS8000® family storage systems, the maximum prefix length is five characters. The maximum prefix length for other systems is 20 characters.

For IBM Storage Virtualize family storage systems, the CSI prefix is added as default if not specified by the user.

• The virt_snap_func parameter is optional but necessary in IBM Storage Virtualize storage systems if using the Snapshot function. To enable the Snapshot function, set the value to "true". The default value is "false". If the value is "false" the snapshot will use the FlashCopy function.

When electing to set the optional "virt_snap_func" parameter, it must also be set with an identical value in the relevant StorageClass yaml.

• To create a stretched snapshot on SAN Volume Controller storage systems, put a colon (:) between the two pools within the pool value. For example:

  pool: demo-pool1:demo-pool2

The two pools must be from different sites.

For more information about stretched snapshot limitations and requirements, see Limitations and Compatibility and requirements.

apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshotClass
metadata:
  name: demo-volumesnapshotclass
driver: block.csi.ibm.com
deletionPolicy: Delete
parameters:
  pool: demo-pool                    # Optional. Use to create the snapshot on a different pool than the source.
  SpaceEfficiency: thin              # Optional. Use to create the snapshot with a different space efficiency than the source.
  snapshot_name_prefix: demo-prefix  # Optional.
  virt_snap_func: "false"            # Optional. Values "true"/"false". The default is "false". If set, this value MUST be identical to the value set in the StorageClass yaml

  csi.storage.k8s.io/snapshotter-secret-name: demo-secret
  csi.storage.k8s.io/snapshotter-secret-namespace: default

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

kubectl apply -f <filename>.yaml

The volumesnapshotclass.snapshot.storage.k8s.io/<volumesnapshotclass-name> created message is emitted.