HP XP7 Storage - Manual (Page 15)

You can judge whether the Reverse Restore function can be used by examining the results of the
FLASHCOPY QUERY RELATIONS command of ICKDSF. For details, see
(page 68) .
When you perform the Reverse Restore function, only the updated data is copied from newly
specified S-VOL (former T-VOL) to T-VOL (former S-VOL) as with ordinary re-establishment. The
updated Data 2A in the target volume is then lost.
The following figure shows the workflow that occurs from establishing the Compatible FlashCopy
relationship by the Incremental FlashCopy function to the executing of the update copy operation
(Reverse Restore).
Figure 10 Performing Reverse Restore
Fast Reverse Restore function
The Fast Reverse Restore function, available for both FCv2 and FCSE, enables you to simplify data
recovery in a time of disaster. This recovery function reverses the original S-VOL and T-VOL
relationship established by the Compatible FlashCopy relationships function. This reversal
re-establishes the relationship with the data flowing in the opposite direction. The Fast Reverse
Restore function is available for FCSE only if the Incremental FlashCopy function is not in use.
The Fast Reverse Restore function cannot be performed in the following cases:
•
If the relationships to be reversed include a relationship established with multiple volumes.
•
If the T-VOL capacity exceeds the S-VOL capacity in the relationship to be reversed.
•
If the original relationship was re-established using the Fast Reverse Restore function.
•
If the original relationship was established with FlashCopy SE and the Incremental FlashCopy
function is in use. Note that a relationship using Incremental FlashCopy cannot be created
using FCSE, so this describes the existence of multiple relationships.
You can perform the Fast Reverse Restore function on a relationship established in NOCOPY mode
or on a relationship during the copy process. If you perform the Fast Reverse Restore function during
the copy process, the copy process will end at that time.
Fast Reverse Restore function 15