Dell PowerVault MD3220 - Manual (Page 148)

148 Configuration: Premium Feature—Snapshot Virtual Disks
The destination of a snapshot repository virtual disk is determined based on
the free capacity available in the disk group. A snapshot repository virtual disk
requires a minimum 8 MB of free capacity. You can choose your preferred
creation path—simple or advanced—if the disk group of the source virtual
disk has the required amount of free space.
If 8 MB of free capacity is not available in the disk group of the source virtual
disk, the Create Snapshot Virtual Disks feature defaults to the advanced path
(see "Creating a Snapshot Virtual Disk Using the Advanced Path" on
page 146). In the advanced path option, you can choose to place the snapshot
repository virtual disk in another disk group or you can use unconfigured
capacity on the storage array to create a new disk group.
NOTE: You can create concurrent snapshots of a source virtual disk on both the
source disk group and on another disk group.
Before creating a Snapshot Virtual Disk:
• The following types of virtual disks are not valid source virtual disks:
snapshot repository virtual disks, snapshot virtual disks, target virtual disks
that are participating in a virtual disk copy.
NOTE: Virtual Disk Copy is an Advanced (Premium) feature.
• You cannot create a snapshot of a virtual disk that contains unreadable
sectors.
• You must satisfy the requirements of your host operating system for
creating snapshot virtual disks. Failure to meet the requirements of your
host operating system results in an inaccurate snapshot of the source
virtual disk or the target virtual disk in a virtual disk copy.
NOTE: Before you create a new snapshot of a source virtual disk, stop any data
access (I/O) activity or suspend data transfer to the source virtual disk to ensure
that you capture an accurate snapshot of the source virtual disk. Close all
applications, including Windows Internet Explorer, to make sure all I/O activity has
stopped.
NOTE: Removing the drive letter of the associated virtual disk(s) in Windows or
unmounting the virtual drive in Linux helps to guarantee a stable copy of the drive
for the Snapshot.
Before creating a snapshot virtual disk, the host server must be in the proper
state. To prepare your host server:
1 Stop all I/O activity to the source.
book.book Page 148 Tuesday, June 18, 2013 2:53 PM