IBM DS8882F, Introduction And Planning Manual, Page: 58 / 164

Multiple Relationship FlashCopy
Allows a source volume to have multiple (up to 12) target volumes at the
same time.
Persistent FlashCopy
Allows the FlashCopy relationship to remain even after the FlashCopy
operation completes. You must explicitly delete the relationship.
Refresh target volume
Refresh a FlashCopy relationship, without recopying all tracks from the
source volume to the target volume.
Resynchronizing FlashCopy volume pairs
Update an initial point-in-time copy of a source volume without having to
recopy your entire volume.
Reverse restore
Reverses the FlashCopy relationship and copies data from the target
volume to the source volume.
Reset SCSI reservation on target volume
If there is a SCSI reservation on the target volume, the reservation is
released when the FlashCopy relationship is established. If this option is
not specified and a SCSI reservation exists on the target volume, the
FlashCopy operation fails.
Remote Pair FlashCopy
Figure 5 on page 49 illustrates how Remote Pair FlashCopy works. If
Remote Pair FlashCopy is used to copy data from Local A to Local B, an
equivalent operation is also performed from Remote A to Remote B.
FlashCopy can be performed as described for a Full Volume FlashCopy,
Incremental FlashCopy, and Dataset Level FlashCopy.
The Remote Pair FlashCopy function prevents the Metro Mirror
relationship from changing states and the resulting momentary period
where Remote A is out of synchronization with Remote B. This feature
provides a solution for data replication, data migration, remote copy, and
disaster recovery tasks.
Without Remote Pair FlashCopy, when you established a FlashCopy
relationship from Local A to Local B, by using a Metro Mirror primary
volume as the target of that FlashCopy relationship, the corresponding
Metro Mirror volume pair went from “full duplex” state to “duplex
pending” state if the FlashCopy data was being transferred to the Local B.
The time that it took to complete the copy of the FlashCopy data until all
Metro Mirror volumes were synchronous again, depended on the amount
of data transferred. During this time, the Local B would be inconsistent if a
disaster were to have occurred.
Note: Previously, if you created a FlashCopy relationship with the
Preserve Mirror, Required option, by using a Metro Mirror primary
volume as the target of that FlashCopy relationship, and if the status of the
Metro Mirror volume pair was not in a “full duplex” state, the FlashCopy
relationship failed. That restriction is now removed. The Remote Pair
FlashCopy relationship completes successfully with the “Preserve Mirror,
Required” option, even if the status of the Metro Mirror volume pair is
either in a suspended or duplex pending state.
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DS8882F Introduction and Planning Guide