Administrator Guide

• If you are using the data on the target virtual disk to copy back to the source virtual disk of a disabled or failed snapshot virtual disk.
If you decide not to preserve the data on the target virtual disk after the virtual disk copy is complete, change the write protection setting
for the target virtual disk to Read/Write.
Virtual disk copy restrictions
Before you perform any virtual disk copy tasks, understand and adhere to the restrictions listed in this section. The restrictions apply to
the source virtual disk, the target virtual disk, and the storage array.
• While a virtual disk copy has a status of In Progress, Pending, or Failed, the source virtual disk is available for read I/O activity only.
After the virtual disk copy is complete, read and write I/O activity to the source virtual disk are permitted.
• A virtual disk can be selected as a target virtual disk for only one virtual disk copy at a time.
• A virtual disk copy for any virtual disk cannot be mounted on the same host as the source virtual disk.
• Windows does not allow a physical disk letter to be assigned to a virtual disk copy.
• A virtual disk with a Failed status cannot be used as a source virtual disk or target virtual disk.
• A virtual disk with a Degraded status cannot be used as a target virtual disk.
• A virtual disk participating in a modification operation cannot be selected as a source virtual disk or target virtual disk. Modification
operations include the following:
○ Capacity expansion
○ RAID-level migration
○ Segment sizing
○ Virtual disk expansion
○ Defragmenting a virtual disk
NOTE:
The following host preparation sections also apply when using the virtual disk copy feature through the
CLI interface.
Creating a virtual disk copy
CAUTION:
Possible loss of data—Source virtual disks that are participating in a virtual disk copy are available for read
I/O activity only while a virtual disk copy has a status of In Progress or Pending. Write requests are allowed after the
virtual disk copy has completed. If the source virtual disk has been formatted with a journaling file system, any attempt
to issue a read request to the source virtual disk may be rejected by the storage array, and an error message may
appear. The journaling file system driver issues a write request before it attempts to issue the read request. The storage
array rejects the write request, and the read request may not be issued due to the rejected write request. This condition
may result in an error message appearing, which indicates that the source virtual disk is write protected. To prevent this
issue from occurring, do not attempt to access a source virtual disk that is participating in a virtual disk copy while the
virtual disk copy has a status of In Progress. Also, make sure that the Read-Only attribute for the target virtual disk is
disabled after the virtual disk copy has completed to prevent error messages from appearing.
The Virtual Disk Copy premium feature includes these items:
• The Create Copy Wizard, which assists in creating a virtual disk copy
• The Copy Manager, which monitors virtual disk copies after they are created
Setting read/write permissions on target virtual disk
To set read/write permissions on the target virtual disk:
1. In the AMW, click Storage & Copy Services.
2. Select Copy Services > Virtual Disk Copy > Manage Copies.
The Copy Manager window is displayed.
3. Select one or more copy pairs in the table.
4. Perform one of these actions:
• To enable Read-only permission, select Change > Target Virtual Disk Permissions > Enable Read-Only.
NOTE:
Write requests to the target virtual disk are rejected when the Read-only permission is enabled on the
target virtual disk.
• To disable Read-only permission, select Change > Target Virtual Disk Permissions > Disable Read-Only.
Premium feature—virtual disk copy
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