Dell PowerVault MD3000 - Manual (Page 48)

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Using Your RAID Enclosure
Target Virtual Disk — When you start a virtual disk copy, the target virtual disk maintains a copy of the
data from the source virtual disk. You can choose whether to use an existing virtual disk or create a new
virtual disk as the target virtual disk. If you choose an existing virtual disk as the target, all data on the
target is overwritten. A target virtual disk can be a standard virtual disk or the source virtual disk of a
failed or disabled snapshot virtual disk.
NOTE:
The target virtual disk capacity must be equal to or greater than the source virtual disk capacity.
When you begin the disk copy process, you must define the rate at which the copy is completed. Giving
the copy process top priority will slightly impact I/O performance, while giving it lowest priority will
make the copy process take longer to complete. You can modify the copy priority while the disk copy is in
progress.
You can find more details on using the virtual disk copy feature in the MD Storage Manager User’s Guide.
Virtual Disk Recovery
You can use the Edit host-to-virtual disk mappings feature to recover data from the backup virtual disk.
This functionality enables you to unmap the original source virtual disk from its host, then map the
backup virtual disk to the same host.
Ensure that you record the LUN used to provide access to the source virtual disk. You will need this
information when you define a host-to-virtual disk mapping for the target (backup) virtual disk. Also, be
sure to stop all I/O activity to the source virtual disk before beginning the virtual disk recovery procedure.
Using Snapshot and Disk Copy Together
You can use the Snapshot Virtual Disk and Virtual Disk Copy premium features together to back up data
on the same storage array, or to restore the data on the snapshot virtual disk to its original source virtual
disk.
You can copy data from a virtual disk in one of two ways:
• By taking a point-in-time snapshot of the data
• By copying the data to another virtual disk using a virtual disk copy
You can select a snapshot virtual disk as the source virtual disk for a virtual disk copy. This configuration
is one of the best ways you can apply the snapshot virtual disk feature, since it enables complete backups
without any impact to the storage array I/O.
You cannot, however, use a snapshot repository virtual disk as a source virtual disk or as a target virtual
disk in a virtual disk copy. If you select the source virtual disk as the target virtual disk of a virtual disk
copy, you must disable all snapshot virtual disks associated with the source virtual disk.