HP StorageWorks Storage Mirroring Recover User's Guide (T5437-96008, November 2009)

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● Checksum—(Default) This option performs a checksum comparison
calculation. A checksum calculation is a formula applied to blocks of data to
determine if the binary make-up of the block is identical. If the checksums on
the source and target machine are the same, the block is skipped. If the
checksums on the source and target machine are not the same, the block on
the source is sent to the target. With this option, the entire file is not
overwritten; only the block that is received from the source is overwritten.
6. Click Initiate Failback to begin the failback process. The restoration will begin and
the Protection Status will display the progress of the restoration. If you selected
Prompt prior to failback, when the restoration is complete a prompt will appear
asking if you want to failback. Click Yes to failback to the source.
During restoration, the Application Manager will display the percent complete. Although
the Application Manager does not display restoration statistics, you can view the
connection and current status statistics through the Replication Console.
Next step:Re-enable protection
Failing back using identity
If you have not done so already, launch the Storage Mirroring Recover Application
Manager by selecting Storage Mirroring Recover Application Manager.
The following sections describe the manual processes you can use to manage failover,
failback, and restoration. These manual processes are required if you chose to perform
Identity failover.
You will be using the Replication Console, Failover Control Center, and/or Text Client to
manage identity failback.
Failback and restoration
If your source experiences a failure, such as a power, network, or disk failure, your target
machine will stand in for the source while you resolve the source machine issues.
During the source machine downtime, data is updated on the target machine. When your
source machine is ready to come back online, the data is no longer current and must be
updated with the new data from the target machine.
Before you begin to restore to the original source, resolve the issue(s) that caused the
failure.
If the source server has to be rebuilt, follow the instructions in Rebuilding the source.
Recovering to the original source
1. After repairing/rebuilding the source server offline, bring the server up but leave the
network connection disabled by unplugging the cable or disabling the network
interface adapter.