Dell POWERVAULT MD3600I - Manual (Page 165)

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Premium Feature—Virtual Disk Copy
NOTE: A virtual disk copy overwrites data on the target virtual disk. Before starting a virtual disk copy, ensure that
you no longer need the data or back up the data on the target virtual disk.
NOTE: If you ordered this feature, you received a Premium Feature Activation card that shipped in the same box as
your Dell PowerVault MD Series storage array. Follow the directions on the card to obtain a key file and to enable
the feature.
NOTE: The preferred method for creating a virtual disk copy is to copy from a snapshot virtual disk. This allows the
original virtual disk used in the snapshot operation to remain fully available for read/write activity while the
snapshot is used as the source for the virtual disk copy operation.
When you create a virtual disk copy, you create a copy pair that has a source virtual disk and a target virtual disk on the
same storage array.
The source virtual disk is the virtual disk that contains the data you want to copy. The source virtual disk accepts the
host I/O read activity and stores the data until it is copied to the target virtual disk. The source virtual disk can be a
standard or thin virtual disk.
The target virtual disk is a standard or thin virtual disk in a disk group or disk pool and, if the legacy version is enabled, a
legacy snapshot base virtual disk.
Reasons to use virtual disk copy include:
• Copying data for improved access — As your storage requirements for a virtual disk change, you can use a
virtual disk copy to copy data to a virtual disk in a disk group that uses drives with larger capacity within the
same storage array. Copying data for larger access capacity enables you to move data to greater capacity
physical disks (for example, 61 GB to 146 GB).
• Restoring snapshot virtual disk data to the source virtual disk — The Virtual Disk Copy feature enables you first
to restore the data from a snapshot virtual disk and then to copy the data from the snapshot virtual disk to the
original source virtual disk.
• Copying data from a thin virtual disk to a standard virtual disk residing in the same storage array. However, you
cannot copy data in the opposite direction (from a standard virtual disk to a thin virtual disk).
• Creating a backup copy — The Virtual Disk Copy feature enables you to create a backup of a virtual disk by
copying data from one virtual disk (the source virtual disk) to another virtual disk (the target virtual disk) in the
same storage array, minimizing the time that the source virtual disk is unavailable to host write activity. You can
then use the target virtual disk as a backup for the source virtual disk, as a resource for system testing, or to
copy data to another device, such as a tape drive or other media.
NOTE: Recovering from a backup copy—You can use the Edit Host-to-Virtual Disk Mappings feature to
recover data from the backup virtual disk you created in the previous procedure. The Host Mappings
option enables you to unmap the source virtual disk from its host and then to map the backup virtual disk to
the same host.
Using Virtual Disk Copy With Snapshot Or Snapshot (Legacy)
Premium Feature
After completion of the virtual disk copy of a snapshot (Legacy), the legacy snapshot is disabled. After completion of the
virtual disk copy using a snapshot image, the snapshot image is deleted and the snapshot virtual disk is disabled.
Snapshots created using older (Legacy) premium feature versions cannot be managed using newer snapshot premium
feature options. Also, a virtual disk in a snapshot group cannot be a target for a virtual disk copy. If you want to choose
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