HP StorageWorks XP Remote Web Console Software - Manual (Page 24)

Pairresync operation time depends on the pair status, PSUS or PSUE. The relationship between the pair
status and the time required for pairresync operations are as follows:
• Pairresync for PSUS pair
When a normal/quick pairresync operation is performed on a split pair (status = PSUS), the
storage system copies all differential tracks from the P-VOL to the S-VOL. When a reverse or
quick restore pairresync operation is performed on a split pair, the storage system copies all
differential tracks from the S-VOL to the P-VOL. This ensures that the P-VOL and S-VOL are
properly resynchronized in the desired direction, and also greatly reduces the time needed
to resynchronize the pair.
• Pairresync for PSUE pair
When a normal/quick pairresync operation is performed on a suspended pair (status = PSUE),
the storage system copies all data on the P-VOL to the S-VOL, since all P-VOL tracks were regarded
as difference data when the pair was suspended. The normal pairresync operation for suspended
pairs is equivalent to and takes as long as the Business Copy initial copy operation. If you
perform the quick pairresync operation on the suspended pairs, the update copy operation will be
performed and all the data will be copied to the S-VOL. In this case, the update copy operation
takes more time than the initial copy because it is combined with new updates from the P-VOL.
Delete Pair Operation
The Business Copy pairsplit-S operation (delete pair) stops the Business Copy copy operations to the
S-VOL of the pair and changes the pair status of both volumes to SMPL. A Business Copy pair can be
deleted by the user at any time except during the quick pairsplit operation (that is, any status except
SMPL and PSUS(SP)). After you delete a Business Copy pair, the S-VOL is still not available for write
operations until the reserve attribute is reset.
The S-VOL of a duplex pair (PAIR status) may not be identical to its P-VOL, due to the asynchronous
Business Copy update copy operations. See “ Deleting Pairs ” on page 83 for instructions on synchronizing
the volumes before deleting the pair.
Pair Status
Figure 8 on page 25 illustrates the Business Copy pair status transitions and the relationship between
the pair status and the Business Copy operations.
24 About Business Copy Operations