HP XP7 for Compatible FlashCopy Mirroring User Guide (TK940-96001)

Figure 9 Incremental FlashCopy
The previous figure shows Data 2A managed as differential data. If you re-execute the command
to establish the relationship, only the differential data of Data 2A is copied to the T-VOL.
However, you cannot perform the Restore function:
When the original relationship was established without using the Incremental FlashCopy
function.
When the original relationship was re-established by the Fast Reverse Restore function, and
then the relationship was re-established by the Restore function twice more.
For details about Fast Reverse Restore function, see (page 15).
Reverse Restore function (Compatible FlashCopy only)
The Reverse Restore function 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 Incremental
FlashCopy function. This reversal re-establishes the relationship with the data flowing in the opposite
direction. However, you cannot perform the Reverse Restore function in the following cases:
If the original relationship was established without using the Incremental FlashCopy function.
If a copy operation established in COPY mode is not yet completed.
If the original relationship was established in NOCOPY mode.
If the relationship being reversed includes a relationship established with multiple volumes.
If the T-VOL capacity exceeds the S-VOL capacity in the relationship being reversed.
If the original relationship was re-established using the Fast Reverse Restore function.
For details about Fast Reverse Restore function, see (page 15).
14 About Compatible FlashCopy