Reversing a FlashCopy relationship using DS CLI

Complete this task to reverse the direction of a FlashCopy^® volume pair.

When the direction of a FlashCopy relationship is reversed, the volume that was previously defined as the target becomes the source for the volume that was previously defined as the source. The data that has changed is copied to the volume that was previously defined as the source. For example, suppose you create a FlashCopy relationship between source volume A and target volume B. Data loss occurs on source volume A. To keep applications running, you can reverse the FlashCopy relationship so that data on volume B is copied to volume A.

The background copy process must complete before you can reverse the direction of the FlashCopy relationship.

Exception: You cannot reverse the direction of the FlashCopy relationship during recovery from the failure of FlashCopy consistency group formation in a Global Mirror configuration due to a failure at the Global Mirror primary site. In this case, after you ensure the consistency of the FlashCopy consistency group target volumes, you can use the fast option of the reverseflash command before the background copy process completes to reverse the direction of the FlashCopy volume pair.

You can perform this task using either the DS CLI or the DS Storage Manager.

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

Issue the reverseflash command to reverse the direction of FlashCopy relationships. Enter the reverseflash command at the dscli command prompt with the following parameters and variables:

dscli>reverseflash -dev storage_image_ID sourcevolumeID:targetvolumeID

Example

dscli>reverseflash IBM.1750-68FA120/0100:IBM.1750-68FA120/0200

The resulting output

Date/Time: Sun Aug 11 02:23:49 PST 2004 IBM DS CLI Version: 5.0.0.0  
DS: IBM.1750-68FA120

FlashCopy pair IBM.1750-68FA120/0100:IBM.1750-68FA120/0200 
successfully reverse restored.