Administrator Guide

Creating snapshot group
A snapshot group is a sequence of point-in-time images of a single associated base virtual disk. A snapshot group uses a repository to save
data for all snapshot images contained in the group. The repository is created at the same time the snapshot group is created.
Keep these guidelines in mind when creating a snapshot group:
• When a base virtual disk that contains a snapshot group is added to an asynchronous remote replication group, the system
automatically changes the repository full policy to automatically purge the oldest snapshot image and sets the autodelete limit to the
maximum allowable snapshot limit for a snapshot group.
• If the base virtual disk resides on a standard disk group, the repository members for any associated snapshot group, can reside on
either a standard disk group or a disk pool. If a base virtual disk resides on a disk pool, all repository members for any associated
snapshot group must reside on the same disk pool as the base virtual disk.
• You cannot create a snapshot group on a failed virtual disk.
• If you attempt to create a snapshot image, that snapshot image creation operation might remain in a Pending state because of the
following conditions:
○ The base virtual disk that contains this snapshot image is a member of an asynchronous remote replication group.
○ The base virtual disk is in a synchronizing operation. The snapshot image creation completes when the synchronization operation is
complete.
1. From the AMW, select the base virtual disk whose data you want to copy.
2. Select a base virtual disk and then select Copy Services > Snapshot Group > Create.
The Snapshot Group Settings window is displayed.
3. In the Snapshot group name field, enter a unique name (30 character maximum) that best describes the virtual disk selected for this
group. For example, AccountingData.
By default, the snapshot group name is shown in the name text box as:[base-virtual disk-name] - SG + sequence-
numberIn this example, SG (snapshot group) is the appended suffix and sequence-number is the chronological number of the
snapshot group relative to the base virtual disk.
For example, if you create the first snapshot group for a base virtual disk called “Accounting”, the default name of the snapshot group
is “Accounting_SG_01”. The default name of the next snapshot group you create based on “Accounting” is “Accounting_SG_02”.
4. Select Create the first Snapshot Image Now to take the first copy of the associated base virtual disk at the same time the
snapshot group is created.
5. Do one of the following to select how you want to create the snapshot group repository:
• Select Automatic and click Finish to create the snapshot group repository with the default capacity settings. This option is the
recommended one.
• Select Manual and click Next to define the properties for the snapshot group repository; then click Finish to continue with the
snapshot group creation process.
NOTE:
Use this option if you want to specify all the customizable settings for the snapshot group repository. The
Manual method is considered advanced and only those who understand physical disk consistency and optimal
physical disk configurations should use this method. See Creating The Snapshot Group Repository (Manually) for
instructions on how to set the repository parameters.
6. Click Finish.
The system performs the following actions:
• The snapshot group and its properties under the individual virtual disk node for the associated base virtual disk are displayed in the
navigation tree.
• If Create the first Snapshot Image Now was selected, the system takes a copy of the associated base virtual disk and the
Snapshot Image Successfully Created window is .
Manually creating a consistency group repository
During the creation of a consistency group, a consistency group repository is created to store the data for all the snapshot images
contained in the group. A consistency group's repository is created initially with one individual repository virtual disk.Each virtual disk that
belongs to a consistency group is referred to as a member virtual disk. When you add a virtual disk to a consistency group, the system
automatically creates a new snapshot group that corresponds to this member virtual disk. A consistency group repository must be created
for every member virtual disk in the consistency group to save the data for all the snapshot images contained in the group.
The Manual method is considered advanced and only those who understand physical disk consistency, provisioning, and optimal physical
disk configurations should use this method.
Premium feature—Snapshot Virtual Disk
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