IBM XIV Storage System

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When IBM® Storage Protect Snapshot creates a backup on an IBM XIV® Storage System, a snapshot of all source volumes that belong to the protected application is created on the storage system. By default, this snapshot is a space-efficient read-only copy of the application.

If you set the USE_WRITABLE_SNAPSHOTS parameter to NO, the snapshots are not mounted directly on a backup host. Instead, IBM Storage Protect Snapshot creates duplicates from the snapshots as part of the mount procedure, and these duplicates are removed when the backup is unmounted. The duplicate is a space-efficient logical copy of the snapshot, and this copy is writable. The duplicate is effectively another image, so changes to the duplicate are not reflected in the snapshot. As a result, the mounted image can be altered without affecting the backup image and any subsequent restore operations of that backup. A subsequent mount operation presents the image as created when the snapshot occurred.

The USE_WRITABLE_SNAPSHOTS parameter specifies whether writable snapshots can be used for mount or restore operations. If writable snapshots are used, no duplicates are created during mount operations and all changes that are applied to the snapshot are preserved. For more information, see LVM mirroring environments. A typical IBM Storage Protect Snapshot profile section for IBM XIV Storage System is provided here:

>>> 
DEVICE_CLASS                     XIV01
COPYSERVICES_HARDWARE_TYPE       XIV
PATH_TO_XCLI                     path where XCLI is installed
COPYSERVICES_SERVERNAME          xiv_hostname
COPYSERVICES_USERNAME            admin
COPYSERVICES_REMOTE              YES
COPYSERVICES_PRIMARY_SERVERNAME  xiv_hostname
COPYSERVICES_REMOTE_SERVERNAME   xiv_remote_hostname
COPYSERVICES_REMOTE_USERNAME     admin
USE_WRITABLE_SNAPSHOTS           AUTO
BACKUP_HOST_NAME                 backup_host
<<<

For remote mirroring with an XIV storage system, each backup copy uses space on the remote site storage and on the local site until it is deleted.

Dependent software packages

IBM Storage Protect Snapshot requires the IBM XIV Storage System command-line interface (XCLI) to be installed on all hosts. That is the production, backup, or clone servers where IBM Storage Protect Snapshot is installed.

Support for LVM mirroring (AIX only)

If AIX Logical Volume Manager (LVM) mirroring is used in the environment, IBM Storage Protect Snapshot can create separate snapshots of either mirror.

IBM Storage Protect Snapshot uses IBM XIV Storage System capabilities to restore writable snapshots. For writable snapshots, a mount operation directly mounts the original snapshot to another host. All changes to the snapshot are preserved, and a subsequent mount or backup operation contains all changes that occurred to the snapshot while mounted. For more information about using writable snapshots, see information about the USE_WRITABLE_SNAPSHOTS parameter in DEVICE_CLASS section.

(AIX only) Support for virtual I/O

IBM XIV Storage System and IBM Storage Protect Snapshot support virtual I/O with n-port ID virtualization. On the production server, IBM Storage Protect Snapshot supports virtual I/O with N_Port ID Virtualization (NPIV) and Virtual I/O Server (VIOS). There is a one-to-one relationship between the virtual I/O logical volume and the storage LUN. On the backup server, IBM Storage Protect Snapshot supports virtual I/O with NPIV only.

Best practices for IBM Storage Protect Snapshot with IBM XIV 11.6 Real-time Compression™

You can use IBM XIV 11.6 Real-time Compression with IBM Storage Protect Snapshot. The usage of IBM Storage Protect Snapshot with compressed volumes is not changed. However, when you transform volumes that are managed by IBM Storage Protect Snapshot from the uncompressed state to the compressed state (or if you transform from compressed to uncompressed), use the following list of behaviors as a guide:
  1. When source volume transformation is in progress (from uncompressed to compressed, or compressed to uncompressed), most IBM Storage Protect Snapshot operations (for example, back up, restore, and mount) fail. The XIV adapter returns the FMM18137E message. Run the volume transformation at a time that does not overlap with scheduled backups or other IBM Storage Protect Snapshot actions that run on the volume that is being transformed.
  2. With the XIV system, you can transform a volume from uncompressed to compressed state (or compressed to uncompressed state) by using one of the following options:
    • With the delete_source=yes option, delete all volume backups. If you do not delete the volume backups, the transform is unsuccessful. You can use the IBM Storage Protect Snapshot to manually delete the backups before the transform operation runs.
    • With the delete_source=no option, the volume backups are retained. After the transform completes, the original (source) volume is hidden from the host system. The original volume is replaced by the transformed volume. Any instant restore operation that completes with the backups made before the transformation are restored to the hidden volume on the storage device. The restore is not made to the volume seen by the host. Note the restore to the volume that is seen by the host appears to be successful, but the source volume visible to the host system is unchanged.
    When you use IBM Storage Protect Snapshot to protect volumes to be transformed, delete the existing snapshot backups, regardless of the delete_source option setting.