Administrator Guide

Using unconfigured capacity
You can increase the capacity of a standard virtual disk or a snapshot repository virtual disk using the unconfigured capacity when no free
capacity exists on a disk group. An increase is achieved by adding unconfigured capacity, in the form of unassigned physical disks, to the
disk group of the standard virtual disk or the snapshot repository virtual disk. See Disk Group Expansion.
Disk group migration
Disk group migration allows to you to migrate a disk group by exporting a disk group and then importing it to another storage array. You
can also export a disk group to store data offline.
When you export a disk group, all the physical disks become offline. To ensure that the export is successful, at least two physical disks
that are not part of the disk group you are migrating must be present in the storage array.
When you migrate the exported disk group to the new storage array, the import fails if a majority of the physical disks are not present in
the group. For example, both the physical disks in a two-disk RAID 1 configuration, or three physical disks (one from each disk pair) in a
four-disk RAID 10 configuration must be present.
Export disk group
The export disk group operation prepares the physical disks in the disk group for removal. You can remove the physical disks for offline
storage, or you can import the disk group to a different storage array. After you complete the export disk group operation, all of the
physical disks are offline. Any associated virtual disks or free capacity nodes are no longer shown in the MD Storage Manager.
Non-exportable components
You must remove or clear any non-exportable settings before you can complete the export disk group procedure. Remove or clear the
following settings:
• Persistent reservations
• Host-to-virtual disk mappings
• Virtual disk copy pairs
• Snapshot virtual disks and snapshot repository virtual disks
• Remote replicated pairs
• Replication repositories
Exporting a disk group
On the source storage array:
1. Save the storage array configuration.
2. Stop all I/O, and unmount or disconnect the file systems on the virtual disks in the disk group.
3. Back up the data on the virtual disks in the disk group.
4. Locate the disk group, and label the physical disks.
5. Place the disk group offline.
6. Obtain blank physical disk modules or new physical disks.
On the target storage array, verify that:
• The target storage array has available physical disk slots.
• The target storage array supports the physical disks that you import.
• The target storage array can support the new virtual disks.
• The latest version of firmware is installed on the RAID controller module.
Import disk group
The import disk group operation adds the imported disk group to the target storage array. After you complete the import disk group
operation, all of the physical disks have Optimal status. Any associated virtual disks or free capacity nodes are now shown in the MD
Storage Manager installed on the target storage array.
NOTE: You lose access to your data during the export/import process.
82 Disk groups, standard virtual disks, and thin virtual disks