DELL 34XX User Manual

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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.
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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 completed successfully for all of the consistency group members, 
the operation fails and new snapshot images are not created.
Normally, all members of a snapshot consistency group will have the same number of snapshot images. 
When you add a new member to a snapshot consistency group, that new member lacks the snapshot 
images that were previously created on the established members of the snapshot consistency group. This 
is not an error condition. Requests for deletion or rollback of snapshot images that exist on only a subset 
of the snapshot consistency group members affects only those members for which the specified 
snapshot image actually exists.
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