HP XP P9500 Storage - Manual (Page 46)

The P-VOL and S-VOL are synchronized when the pair status changes from PSUS(SP)/PSUS or
COPY(SP)/COPY to PSUS.
Related information
•
“Types of split operations” (page 46)
•
“Prerequisite information for splitting pairs” (page 46)
•
“Splitting pairs” (page 47)
•
“Splitting pairs in a consistency group using consistency group pair-split workflow” (page 47)
Types of split operations
Four options are available when splitting a pair:
•
Steady split, which copies all differential data to the S-VOL and then splits the pair.
•
Quick split, in which the pair is immediately split, so that the S-VOL is immediately available
for read and write I/O. Remaining differential data is copied to the S-VOL in the background.
•
Consistency group pair-split, in which all pairs in a consistency group are split at the same
time. RAID Manager is required for this operation.
Prerequisite information for splitting pairs
•
Pair status must be one of the following:
PAIR when splitting an existing pair. ◦
◦ SMPL, when creating and immediately splitting an L1 pair.
◦ To split an L1 pair that has L2 pairs, check “Status for L1, L2 pairs and operations
permitted” (page 55) .
◦ PSUS for the L1 pair when splitting, or creating and immediately splitting, an L2 pair.
•
The P-VOL and S-VOL are synchronized when pair status changes from COPY(SP)/COPY or
PSUS(SP)/PSUS to PSUS.
•
To ensure that the data in the P-VOL matches data in the S-VOL after the pair split, stop write
operations from the host server to the P-VOL before running the operation.
•
For a split operation to complete faster on an existing pair, stop host access to the P-VOL
before starting the split.
Related information
•
“PSUS, performance, and SOM 459” (page 46)
•
“Status for L1, L2 pairs and operations permitted” (page 55)
PSUS, performance, and SOM 459
Performance can be affected for pairs that are in PSUS(SP)/PSUS or COPY(SP)/COPY status
depending on the following:
•
Whether system option mode 459 is enabled
•
Whether the S-VOL is an external or internal volume
•
Whether the S-VOL is a volume in a Dynamic Provisioning pool
46 Performing pair operations