Dell PowerVault MD3200 Owner's Manual - Page 141

Preparing Host Servers to Create the Snapshot Using the Advanced Path

Page 141 highlights

• Percent Full-When the snapshot repository virtual disk reaches the userspecified repository full percentage level, the event is logged in the Major Event Log (MEL). The default snapshot repository full percentage level is 50% of the source virtual disk. • Snapshot Repository Virtual Disk Full Conditions-Choose whether to fail writes to the source virtual disk or fail the snapshot virtual disk when the snapshot repository virtual disk becomes full. • Host-to-Virtual Disk Mapping-Choose whether to map the snapshot virtual disk to a host or host group now or to map the snapshot virtual disk later. The default setting is Map later. Preparing Host Servers to Create the Snapshot Using the Advanced Path NOTE: Before using the Snapshot Virtual Disks Premium Feature in a Microsoft® Windows® clustered configuration, you must first 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. 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 details on mapping the snapshot virtual disk to the secondary node, refer to the Dell™ PowerVault™ MD3200 and MD3220 Storage Arrays With Microsoft® Windows Server® Failover Clusters on support.dell.com/manuals. 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 140). 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. Configuration: Premium Feature-Snapshot Virtual Disks 141

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Configuration: Premium Feature—Snapshot Virtual Disks
141
Percent Full—When the snapshot repository virtual disk reaches the user-
specified repository full percentage level, the event is logged in the Major
Event Log (MEL). The default snapshot repository full percentage level is
50% of the source virtual disk.
Snapshot Repository Virtual Disk Full Conditions—Choose whether to
fail writes to the source virtual disk or fail the snapshot virtual disk when
the snapshot repository virtual disk becomes full.
Host-to-Virtual Disk Mapping—Choose whether to map the snapshot
virtual disk to a host or host group now or to map the snapshot virtual disk
later. The default setting is Map later.
Preparing Host Servers to Create the Snapshot Using the Advanced Path
NOTE:
Before using the Snapshot Virtual Disks Premium Feature in a Microsoft®
Windows® clustered configuration, you must first 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.
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 details on mapping the snapshot virtual disk to the secondary node,
refer to the
Dell™ PowerVault™ MD3200 and MD3220 Storage Arrays With
Microsoft® Windows Server® Failover Clusters
on
support.dell.com/manuals
.
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 140). 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.