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Planning: MD3200i Series Storage Array Terms and Concepts
online and user-accessible. When the backup is completed, the snapshot
virtual disk is no longer needed. You can create up to four snapshots per
virtual disk.
Snapshots are used to recover previous versions of files that have changed
since the snapshot was taken. Snapshots are implemented using a copy-on-
write algorithm, which makes a backup copy of data the instant an error
occurs. Data on a virtual disk is copied to the snapshot repository before it is
modified. Snapshots can be created instantaneously or can be scheduled and
take up less overhead than a full physical copy process.
Snapshot Repository Virtual Disk
When you create a snapshot virtual disk, it automatically creates a snapshot
repository virtual disk. A snapshot repository is a virtual disk created in the
storage array as a resource for a snapshot virtual disk. A snapshot repository
virtual disk contains snapshot virtual disk metadata and copy-on-write data
for a particular snapshot virtual disk. The repository supports one snapshot
only.
You cannot select a snapshot repository virtual disk as a source virtual disk or
as a target virtual disk in a virtual disk copy. If you select a Snapshot source
virtual disk as the target virtual disk of a virtual disk copy, you must disable all
snapshot virtual disks associated with the source virtual disk.
CAUTION:
Before using the Snapshot Virtual Disks Premium Feature in a
Windows Clustered configuration, you must map the snapshot virtual disk to the
cluster node that owns the source virtual disk. This ensures that the cluster nodes
correctly recognize the snapshot virtual disk.
CAUTION:
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 misidentifying the snapshot virtual disk. This can result in
data loss or an inaccessible snapshot.
For more information on mapping the snapshot virtual disk to the secondary
node, see the
Dell PowerVault MD3200i and MD3220i Storage Arrays With
Microsoft Windows Server Failover
Clusters
on
support.dell.com/manuals
.
book.book Page 52 Saturday, September 24, 2011 9:06 AM
Summary of Contents for PowerVault MD3200i Series
Page 18: ...18 Contents ...
Page 22: ...22 Introduction ...
Page 60: ...60 Planning MD3200i Series Storage Array Terms and Concepts ...
Page 148: ...148 Configuration Disk Groups and Virtual Disks ...
Page 172: ...172 Configuration Premium Feature Snapshot Virtual Disks ...
Page 188: ...188 Configuration Premium Feature Upgrading to High Performance Tier ...
Page 200: ...200 Configuration Device Mapper Multipath for Linux ...
Page 236: ...236 Management Firmware Inventory ...
Page 262: ...262 Troubleshooting Your Storage Array Software ...
Page 274: ...274 Getting Help ...
Page 282: ...282 Index ...