DELL MD3220 사용자 설명서

Configuration: Premium Feature—Virtual Disk Copy

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. 

• 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. 

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 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. 

To create a virtual disk copy for a Microsoft Cluster Server (MSCS) shared 

disk, create a snapshot of the virtual disk, and then use the snapshot virtual 

disk as the source for the virtual disk copy.

An attempt to directly create a virtual disk copy for an MSCS shared disk, 

rather than using a snapshot virtual disk, fails with the following error: The 

operation cannot complete because the selected virtual disk is not a source virtual 

disk candidate.

When creating a snapshot virtual disk, map the snapshot virtual disk to only 

one node in the cluster. Mapping the snapshot virtual disk to the host group or both 

nodes in the cluster may cause data corruption by allowing both nodes to 

concurrently access data.

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