Dell MD3220 Computer Accessories User Manual


 
144 Configuration: Premium Feature—Snapshot Virtual Disks
NOTE: Mapping the snapshot virtual disk to the node that does not own the source
virtual disk before the Snapshot enabling process is completed can result in the
operating system mis-identifying the snapshot virtual disk. This, in turn, can result in
data loss on the source virtual disk or an inaccessible snapshot.
NOTE: For more information on mapping the snapshot virtual disk to the secondary
node, see the Dell PowerVault MD3200 and MD3220 Storage Arrays With Microsoft
Windows Server Failover Clusters at support.dell.com/manuals.
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 has to be in the proper
state. To ensure that the host server is properly prepared to create a snapshot
virtual disk, you can either use an application to carry out this task, or you can
perform the following steps:
1
Stop all I/O activity to the source.
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