Dell PowerVault MD3260i - Manual (Page 153)

Notes
A consistency group is a logical entity that enables you to manage in batch form all of the snapshot images that you add
to the collection. The consistency group is a collection of snapshot groups that have mutual consistency requirements
or dependencies for their snapshot images. Any snapshot images that you create and use for this collection must be
managed in accordance with the consistency dependencies.
You can use any combination of alphanumeric characters, underscore (_), hyphen (-), and pound (#) for the names.
Names can have a maximum of 30 characters.
The snapshot images in a consistency group can be deduced based on the existence of a snapshot image within a
consistency group. All snapshot images that reside within a consistency group share a common time stamp and
sequence number.
An operation on a snapshot image consistency group is treated as a single request, and causes all pending I/O
operations to the associated base virtual disk of each member to be drained and suspended before creating the
snapshot images. If creation of the snapshot images cannot be completed successfully for all of the consistency group
members, the operation fails and has no affect (that is, new snapshot images are not created).
Based on this behavior all members for a consistency group usually have the same number of PiTs. However, when a
new member is added to a consistency group, that new member lacks the snapshot images that were previously
created on the established members of the consistency group. This is not considered an error condition. Ensuing
requests for deletion or rollback of snapshot images that only exist on a subset of the consistency group members will
only affect the members for which the specified snapshot images actually exists.
For more information on scheduling snapshot images in a consistency group, see
Scheduling Snapshots .
Create Consistency Group Snapshot Image
Description
This command creates a new snapshot image for each base virtual disk that is a member of a snapshot consistency
group.
Syntax
create cgSnapImage consistencyGroup="consistencyGroupName"
Parameter
Parameter Description
consistencyGroup The name of the consistency group for which you are
creating snapshot images. Enclose the consistency group
name in double quotation marks (" ").
Notes
You can use any combination of alphanumeric characters, hyphens, and underscores for the names. Names can have a
maximum of 30 characters.
The command causes all pending I/O operations to each base virtual disk that is a member of the consistency group to
be drained and suspended before creating the snapshot images. If the creation of all of the snapshot images cannot be
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