Managing cloud volumes

Enable cloud snapshots on volumes

In the management GUI, when you create a snapshot, cloud snapshots are automatically enabled for the volume when the volume is not restricted from cloud snapshots. If you are using the command-line interface, you must enable cloud snapshots for the volume separately.

Cloud snapshot restrictions

A volume cannot be enabled for cloud snapshots if the volume is used in any of the following capacities:

• The volume is a VMware vSphere Virtual Volume.
• A volume has a copy in a different storage pool.
• A volume is being migrated between different storage pools.
• A volume cannot be enabled for cloud snapshots if the cloud storage is set to import mode.
• A volume cannot be enabled for cloud snapshots if the maximum number of cloud volumes already exists.

Note: If the system exceeds this limit, you can disable cloud snapshots on an existing cloud volume and delete its associated snapshots from the cloud storage to accommodate snapshots on new cloud volumes.

• Volume is associated with user-owned legacy FlashCopy® mappings.

Note: Cloud snapshots are supported with the system's new FlashCopy management model based on snapshot function. For more information about snapshot function, see Snapshots.

To enable snapshots on a volume using the command-line interface, see chvdisk command.

Disable cloud snapshots for a volume

If you no longer need to create snapshots for a cloud volume, you can disable the function for the volume with the management GUI or the command-line interface.

When cloud snapshots are disabled on a volume, the volume is disconnected from the cloud account. Existing snapshot versions of the volume that are located in cloud storage are not deleted. A full snapshot of the volume is required if a cloud snapshot is needed later. You cannot disable cloud snapshots on a volume if a current snapshot operation is in progress. You must either wait for the snapshot operation to complete or cancel the snapshot. The cloud snapshots can be used only with volumes that have a capacity greater than zero bytes.

To disable cloud snapshots for a volume, use the Volumes > Cloud Volumes panel in the management GUI. Right -click the volume and select Disable cloud snapshots.

To disable snapshots on a volume using the command-line interface, see chvdisk command.

Create volume groups

For cloud volumes, you can create a group of volumes of which you can create snapshots and transfer to cloud storage. Volumes groups can be created to easily manage cloud snapshots for volumes. It is convenient to provide a single action to take a snapshot of a preset group of volumes.

Volume groups provide consistent snapshot operations for cloud volumes. You can view cloud volumes and display whether the volumes are part of a group in the management GUI, but you must configure the volume group in the command-line interface.

To create volume group, see the mkvolumegroup command, and to create or add cloud volumes to the volume group, see the chvdisk command.

Create cloud snapshots

After you create a cloud account, you can specify an individual volume or groups of volumes to be copied and transferred to cloud storage by creating cloud snapshots.

Cloud snapshots are point-in-time copies of volumes that are created and transferred to cloud storage that is managed by a cloud service provider. You can select individual or multiple volumes to create cloud snapshots of the volume data. You can use the command-line interface to configure volume groups to create snapshots for multiple volumes for consistent management.

When a snapshot is created for multiple volumes or volumes in a group, a separate snapshot operation is started for each individual volume.

In the management GUI, volumes that do not have restrictions are enabled for cloud snapshots when a snapshot is created for that volume. If you are using the command-line interface, you must enable snapshots on the volume before you can create a snapshot of the volume.

To enable snapshots on a volume using the command-line interface, see the chvdisk command and to create cloud snapshots on a volume, see the backupvolume command. If you want to complete a full snapshot where all data on the cloud volume is copied to the cloud storage use backupvolume -full volumen_id_or_name.

Restore cloud snapshots

With transparent cloud tiering enabled, snapshot versions of volumes are stored on the cloud storage that is provided by a supported cloud service provider. You can restore data from the cloud back to the system from any snapshot version to recover from data loss on the system.

A volume cannot be used for restoring data from the cloud if the volume is a VMware vSphere Virtual Volume.

To restore a snapshot generation from cloud storage to the system, use the Volumes > Cloud Volumes panel in the management GUI. Right-click the volume to display all snapshot versions that are available to restore and select Restore and snapshot version that you want to restore to the system.

Select the target volume from the following options:

Restore a production volume group with the contents of one of the volume groups snapshot

The contents of the production system is overwritten with a previously saved version of the data.

Restore to the production volume

The snapshot version is restored to the production volume, which is the original volume from which the snapshots were created. After the restore operation completes, the snapshot version completely replaces the current data that exists on production volume. During the restore operation, the production volume goes offline until it completes. If you do not want to have the production volume offline for the restore, you can restore a cloud snapshot to a new volume. The production volume remains online and host operations are not disrupted.

Restore to a new volume

When the snapshot version is restored to a new volume, you can use the restored data independent of the original volume from which the snapshot was created. If the new volume exists on the system, then the restore operation uses the unique identifier (UID) of the new volume. If the new volume does not exist on the system, you need to choose whether to use the UID from the original volume or create a new UID. If you plan on using the new volume on the same system, use the UID that is associated with the snapshot version that is being restored.

You can use the command-line interface to either restore a snapshot directly to the production volume or to a new volume. To determine the available snapshot versions, see the lsvolumebackupgeneration command.

Restore to a production volume

To restore the most recent or old version of the cloud snapshot to the production volume use restorevolume. To restore an older version of the cloud snapshot, you must specify the -deletelatergenerations parameter to confirm the deletion of all later versions of the snapshot.

Restore to a new volume

You can also restore a snapshot version for a volume that might not exist on the local system. In this case, the unique identifier of the volume snapshot data is used. You can also restore the entire snapshot by replacing the volume UID with the UID of the volume that was originally used for the snapshot. Ensure that the UID is not currently used on any other volume in the system. To restore a snapshot version to the selected volume use the restorevolume command. You must specify -restoreuid to retain the UID for that volume, otherwise it restores data on new volume without replacing volume UID of original volume.

Delete a version of a cloud snapshot

A cloud volume can have multiple versions of snapshots on the cloud storage. If capacity on the cloud becomes limited, you can delete versions of the volume that are no longer necessary.

Before you delete a version of a snapshot, ensure that no snapshot or restore operations are in progress for the selected volume. In addition, ensure that the connection to the cloud service provider is online, so the deletion can be validated and completed on the cloud storage. Wait until these operations complete before you delete any snapshots that are associated with the volume. Deleting a backup generation (as opposed to canceling an in-progress backup) requires the connection to the cloud account to be available when the task is submitted in order to validate user input before you start an asynchronous delete operation.

Before you delete a version of a cloud snapshot, ensure that the connection to the cloud service provider is online. To delete a version of a cloud snapshot from the cloud storage, use the Volumes > Cloud Volumes panel in the management GUI. Right-click the cloud volumes and select Manage Cloud Snapshots and select the version of the snapshot.

To delete a single or all snapshot version for a volume using the command-line interface, see the rmvolumebackupgeneration command.

Import cloud snapshots

You can restore a cloud snapshot for a volume that was backed up from another system to the same container by importing a snapshot version of that volume to the local system.

When you import a cloud snapshot of a volume that is not on the current system, you can choose to use the unique identifier of the snapshot to replace the existing UID on the volume. In this case, the UID of the snapshot replaces the existing UID for the volume that is selected to receive the restored data. Ensure that the new UID is not currently used on any other volume in the system. The management GUI does not support UID replacement when a snapshot is imported from another system.

To import a cloud snapshot from another system,

1. Determine the import system ID for the system that the cloud snapshot is being imported from by running CLI lscloudaccountimportcandidate on the target system.
2. To change the mode of the cloud account, you use different commands based on the type of cloud account that is configured, use CLI chcloudaccountswift, chcloudaccountawss3, chcloudaccountazure. You must specify -mode import and import system ID.
3. Use the restorevolume command to restore the cloud snapshot for the volume that was backed up.
4. To confirm that the cloud account is in import mode, use CLI lscloudaccount. The target system can now access the data that is in the cloud snapshot of the source system.
5. To return the cloud account to normal mode, you use different commands based on the type of cloud account. You must specify -mode normal.