Dell POWERVAULT MD3620I - Manual (Page 174)

174 Configuration: Premium Feature—Snapshot Virtual Disks
NOTE: Failing to follow these additional instructions could create unusable
snapshot virtual disks. For more information, see the PowerVault Modular
Disk Storage Manager online help topics.
• To use this option, the snapshot virtual disk must be either in an Optimal
status or Disabled status.
• When using this option, the previously configured snapshot name
parameters and snapshot repository virtual disk are used.
To recreate the snapshot virtual disk:
1 In the AMW, select the Logical tab, select a snapshot virtual disk.
2 Select Virtual Disk Snapshot Re-create.
3 Type yes, and click OK.
Snapshot Rollback
The snapshot rollback feature allows you to revert the contents of a virtual
disk to match a point-in-time image existing on a snapshot virtual disk.
During a rollback, the host server can still write data to the base virtual disk.
However, the snapshot virtual disk is set as read-only during the rollback
operation and becomes available for write operations immediately after the
rollback is complete. The snapshot virtual disk cannot be restarted, deleted,
or disabled during the rollback operation.
The associated snapshot repository virtual disk must have sufficient capacity
to process the rollback operation and the write operations from the host. At
most, the snapshot repository virtual disk may need twice the size of the base
disk, plus additional metadata space equaling approximately 1/1000th (that
is, 0.1%) of the Base volume capacity.
NOTE: Due to host server write operations, the content in the snapshot virtual disk
may have changed since creation of the snapshot. The rollback operation includes
any changes made to the snapshot after it was created.
You can set priority for a rollback operation. Higher priority allocates more
system resources for the rollback operation and affects overall system
performance.
Rules and Guidelines for Performing a Snapshot Rollback
The following rules and guidelines apply to performing a snapshot rollback:
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