HP XP Racks - Manual (Page 48)

3. In the Change Options dialog box, complete the following and then click OK:
•
For Split Type, select a split type.
Values:
- Non Split: The pair is not split.
- Quick Split: The pair is split and then the differential data is copied so that the S-VOL is
immediately available for read and write I/O. Any remaining differential data is copied
to the S-VOL in the background.
- Steady Split: Differential data is copied and then the pair is split.
Default: Non Split
•
For Copy Pace, select the rate at which you want the XP7 storage system to copy data.
Values:
- Slower: Improved host I/O performance but slower processing speed.
- Medium: Average processing speed and host I/O performance.
- Faster: Faster processing speed but slower host I/O performance.
Default: Medium
Related topics
•
“Pair splitting methods” (page 49) .
Splitting BC Z pairs
Splitting BC Z pairs separates and unpairs the P-VOL and S-VOLs, stops host updates to the P-VOL
and periodic copying to the S-VOL, and makes the S-VOL data available to secondary software
applications.
Splitting an BC Z pair ensures data consistency and ensures that the data in the S-VOL at the time
of the split is consistent and usable. The S-VOL contains a mirror image of the original volume at
that point in time. It is available for read/write access by secondary host applications.
The P-VOL for a split pair continues to be updated, but the S-VOL remains unchanged. The differential
data that accrues while the pair is split is stored the differential bitmaps. Changes to the P-VOL
and S-VOLs are managed in these differential bitmaps. The differential data accrues until you
resynchronize the pair, which copies the differential data to the S-VOL.
If you have assigned an BC Z P-VOL or S-VOL to a volume reserved for Auto LUN, splitting the
volume cancels migration.
If you are splitting BC Z pairs with shared Cnt Ac-S Z or Cnt Ac-J Z volumes, see the restrictions.
If you are sharing BC Z S-VOLs with Cnt Ac-J Z P-VOLs and the R-JNL has a timeout period that
ends after the split time, the storage system may not detect the journal data. In this case, the BC Z
split operation runs after the timeout period.
You set the timeout value according to your requirements.
Default: 6 hours
For more information about the timeout period, see the Business Continuity Manager User Guide.
Related topics
•
“Pair splitting methods” (page 49) .
•
“Prerequisites for splitting BC Z pairs” (page 49) .
•
“Splitting BC Z pairs” (page 50) .
•
“Workflow for consistency group pair-split” (page 52) .
48 Managing Business Copy Z pairs