Creating a consistency group – Dell POWERVAULT MD3600I User Manual

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1.

Select the Storage & Copy Services tab.

2.

Select the storage object for which you want to view the associated physical components and then select

Individual Repository Virtual Disk → View Associated Physical Components.

Creating A Consistency Group

A consistency group is simultaneous snapshots of multiple virtual disks, thus ensuring consistent copies of a group of

virtual disks. 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.

The following guidelines apply:

If the base virtual disk resides on a standard disk group, the repository members for any associated consistency

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 consistency group must reside on the same disk pool as the base virtual

disk.

You cannot create a consistency group on a failed virtual disk.

A consistency group contains one snapshot group for each virtual disk that is a member of the consistency

group. You cannot individually manage a snapshot group that is associated with a consistency group. Instead

you must perform the manage operations (create snapshot image, delete snapshot image or snapshot group,

and rollback snapshot image) at the consistency group level.

If you attempt to create a consistency group snapshot image, the operation might remain in a Pending state

because of the following conditions:

– The base virtual disk that contains this consistency group snapshot image is a member of an

asynchronous remote replication group.

– The base virtual disk is currently in a synchronizing operation. The consistency group snapshot image

creation completes as soon as the synchronization operation is complete.

To create a consistency group:

1.

From the AMW, select the Storage & Copy Services tab.

2.

Select Copy Services → Consistency Group → Create.
The Consistency Group Settings window is displayed.

3.

In the Consistency group name field, enter a unique name (30-character maximum) that best describes the member

virtual disks that you want to add for this group.
By default, the consistency group name is shown in the name text box as:

CG + sequence-number

In this example, CG (Consistency Group) is the prefix and sequence-number is the chronological number of the
consistency group, and is incremented based on how many consistency groups currently exist.

4.

Select if you want to add the member virtual disks to the consistency group now or later:

– Select Add members now and then from the eligible member virtual disks, select the virtual disks that you

want to add as members to the consistency group. If you choose this method, you must create a repository

for each member of the consistency group. Go to step 5. You can click the Select all check box to add all

the virtual disks displayed in the Eligible virtual disks table to the consistency group.

– Select Add members later and then click Finish to create the consistency group without member virtual

disks. Go to step 6.

The Eligible virtual disks table shows only those virtual disks that are capable of being used in the consistency
group. To be eligible to be a member of a consistency group, a virtual disk cannot be in a Failed state and must
contain less than the maximum allowable number of associated snapshot groups.

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