Committing data to FlashCopy target volumes

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Complete this task to commit data to FlashCopy® target volumes to form a consistency group on the target volumes as part of a disaster recovery process.

Before you begin

You can commit changes to FlashCopy target volumes only if you have modified the FlashCopy relationship using the setflashrevertible command, which changes the Revertible value to Enabled. You can use the commitflash command to commit data only when your analysis of the FlashCopy relationships reveals one of the following conditions:
  • All the FlashCopy sequence numbers are equal and at least one of the FlashCopy relationships is nonrevertible.
  • The FlashCopy relationships appear as follows:
    • Some of the FlashCopy relationships completed processing so that a consistent group was created. These FlashCopy relationships are no longer revertible.
    • Some of the FlashCopy relationships have not completed creating a consistency group. These FlashCopy relationships are still in a revertible state.
    • All the FlashCopy relationships have the same FlashCopy sequence number. This indicates that all the FlashCopy relationships are involved in the same consistency group.

About this task

If a FlashCopy consistency group formation operation does not complete, you must verify the consistency group at the remote site and determine whether the changes need to be “rolled forward” (committed) or “rolled backward” (discarded). The commit task specifies that the last consistency group that has been created by the Global Mirror session is committed to the current state, and reverting to the previous consistency group state is no longer possible.

You can complete this task using either the DS CLI or the DS8000® Storage Management GUI.

Complete the following step to correct the applicable FlashCopy relationships with DS CLI commands. The example command in this task is shown in two formats. The first format shows the type of information that the command requires. The second format is an example command with declared values for the variables.

Procedure

Issue the commitflash command to correct the FlashCopy relationships and commit them to the consistency group that was being formed before the disaster occurred. Enter the commitflash command at the dscli command prompt with the following parameters and variables:

dscli> commitflash -dev storage_image_ID SourceVolumeID

Example

dscli> commitflash -dev 
IBM.2107-75FA150 0100
Note:
  • Remember that storage_image_ID is the value for the remote server that has been designated the primary server until the original primary server is again available for use.
  • Global Mirror operations have completed the establish FlashCopy revertible processing and might have failed to form a consistency group before the disaster occurred. If your analysis, through use of the lsflash command, has determined that a commitflash command is needed, there is no need to enter a new mkflash command.

A confirmation message like the following one is generated for each FlashCopy relationship that has been successfully reset.

FlashCopy pair 0100:0200 successfully committed.