HP XP P9500 Storage - Manual (Page 31)

you specify a small number, such as 3, copying is slower, but the impact on I/O performance
is lessened.
7. From the Priority drop-down menu, select the scheduling order for the copy operations. This
applies when multiple pairs are being resynchronized. You can enter between 1-256. The
highest priority is 1, the lowest priority is 256. The default is 32.
8. Click Set.
9. In the Preview list, check the settings. To change a setting, right-click and select Modify. When
satisfied, click Apply.
Update the pair status by clicking File/Refresh, then confirm that the operation is completed with
a status of PAIR. If the operation is still in progress, the status is COPY.
Reverse resynchronization
After a failover, when the S-VOL is receiving updates from the host instead of the P-VOL, you can
resynchronize the P-VOL with the S-VOL using the RAID Manager pairresync -swaps command.
Copy direction is from S-VOL-to-P-VOL.
The pairresync -swaps command is the only supported method for reverse resynchronizing ESAM
pairs.
Prerequisite information:
•
All errors must be cleared before beginning.
•
Pair status must be SSWS.
•
The P-VOL and S-VOL are swapped in this operation: the secondary system S-VOL becomes
the P-VOL; the primary system P-VOL becomes the S-VOL.
Procedure 12 To resynchronize the P-VOL with the S-VOL:
1. Execute the RAID Manager pairresync -swaps command on the S-VOL.
The data in the RCU S-VOL is copied to the MCU P-VOL. Also, the P-VOL and S-VOL is
swapped. The MCU P-VOL becomes the S-VOL, and the RCU S-VOL becomes the P-VOL.
2. When the operation completes, verify that the pair is in PAIR status.
The following figure illustrates swapping of ESAM P-VOL and S-VOL.
Releasing a pair
You can release a pair when you no longer need to keep the P-VOL and S-VOL synchronized.
Prerequisite information:
Releasing a pair 31