Dell POWERVAULT MD3620I Owner's Manual page 165

• 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.
2 Using your Windows system, flush the cache to the source. At the host
prompt, type SMrepassist -f <filename-identifier> and
press <Enter>. For more information, see "SMrepassist Utility" on
page 267.
3 Remove the drive letter(s) of the source in Windows or unmount the
virtual drive(s) in Linux to help guarantee a stable copy of the drive for the
Snapshot. If this is not done, the snapshot operation reports that it has
completed successfully, but the snapshot data is not updated properly.
NOTE:
Summary tab and then click Disk Groups & Virtual Disks.
4 Follow any additional instructions for your operating system. Failure to
follow these additional instructions can create unusable snapshot virtual
disks.
NOTE:
If your operating system requires additional instructions, you can find those
instructions in your operating system documentation.
After your host server is prepared, see "Creating a Snapshot Virtual Disk
Using the Advanced Path" on page 162, to create the snapshot using the
advanced path.
To verify that the virtual disk is in Optimal or Disabled state, select the
Configuration: Premium Feature—Snapshot Virtual Disks
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