Administrator Guide

The following guidelines apply:
• There is a minimum required capacity for a snapshot group repository which depends on your configuration.
• When you define the capacity requirements for a repository, keep in mind any future requirements that you may have for other virtual
disks in this disk group or disk pool. Make sure that you have enough capacity to meet your data storage needs without allocating too
much capacity that takes up the storage in your system.
• The list of repository candidates can contain both new and existing repository virtual disks. Existing repository virtual disks are placed
at the top of the list. The benefit of reusing an existing repository virtual disk is that you can avoid the initialization process that occurs
when you create a new one.
To create a snapshot virtual disk repository:
1. From the Snapshot Virtual Disk Settings window, select Manual and click Next to define the properties for the snapshot virtual
disk repository.
The Snapshot Virtual disk Repository Settings - Manual window is displayed.
2. Choose how you want filter the repository candidates in the Repository candidates table, based on either a percentage of the base
virtual disk capacity or by preferred capacity.
The repository candidates that you selected are displayed.
3. Select the repository, from the Repository candidates table, that you want to use for the snapshot virtual disk and select a
repository candidate that is closest to the capacity you specified.
• The Repository candidates table shows both new and existing repositories that are capable of being used for the snapshot
virtual disk based on the value you specified for percentage or the value you specified for preferred capacity.
• The Difference column shows the mathematical difference between your selected capacity and the actual capacity of the
repository candidate. If the repository candidate is new, then the system uses the exact capacity size that you specified and
displays zero (0) in the Difference column.
4. In the % Full box, define the value that determines when a warning is triggered when the capacity of a snapshot virtual disk repository
reaches the defined percentage.
5. Click Finish.
Changing the settings of a Snapshot Virtual Disk
Use the Change Snapshot Virtual Disk Settings option to modify the repository settings that were configured when you created the
snapshot virtual disk. You can modify the maximum percentage for the snapshot virtual disk repository to set a warning when the capacity
of a snapshot virtual disk repository reaches the defined percentage.
1. From the AMW, select the Storage & Copy Services tab.
2. Select a base virtual disk, and then select Copy Services > Snapshot Virtual disk > Change Settings.
The Change Snapshot Virtual Disk Settings window is displayed.
3. Modify the repository full settings as required.
4. Click OK to apply the changes.
Disabling Snapshot Virtual Disk or consistency group
Snapshot Virtual Disk
Use the Disable option when you want to invalidate a snapshot copy or a consistency group snapshot virtual disk. If the snapshot virtual
disk or consistency group snapshot virtual disk is designated as read-write, this option also allows you to stop any further write activity to
its associated snapshot repository virtual disk.
Use the Disable option if one of these conditions applies:
• You are finished with the snapshot virtual disk or consistency group snapshot virtual disk for the time being.
• You intend to re-create the snapshot virtual disk or consistency group snapshot virtual disk (that is designated as read-write) later and
want to retain the associated snapshot repository virtual disk so that it does not need to be created again.
• You want to maximize the storage array performance by stopping write activity to the snapshot repository virtual disk.
If you decide to re-create the snapshot virtual disk or consistency group snapshot virtual disk, you must choose a snapshot image from
the same base virtual disk.
If you disable the snapshot virtual disk or consistency group snapshot virtual disk, the system performs the following actions:
• Retains the World-Wide Name (WWN) for the snapshot virtual disk or consistency group snapshot virtual disk.
• Retains the snapshot virtual disk or consistency group snapshot virtual disk’s association with the same base virtual disk.
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Premium feature—Snapshot Virtual Disk