HP XP24000/XP20000 Business Copy Software User Guide (T5213-96034, November 2011)

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 XP 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 will take much more time than the initial copy operation.
Delete Pair Operation
The XP Business Copy pairsplit-S operation (delete pair) stops the copy operations to the S-VOL of
the pair and changes the pair status of both volumes to SMPL. An XP 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)).
When a delete pair operation is performed on a pair in PSUS status, the reserve attribute of the
S-VOL is reset automatically.
The S-VOL of a duplex pair (PAIR status) may not be identical to its P-VOL, because of the
asynchronous XP Business Copy update copy operations. See (page 85) for instructions on
synchronizing the volumes before deleting the pair.
CAUTION:
• If you delete a pair, the volume status changes from SMPL(PD) to SMPL. You can check the
volume status in the Pair Operation window.
Although you can check the volume status by using the Pairdisplay command of RAID Manager,
this command does not enable you to distinguish between SMPL and SMPL(PD). To distinguish
between SMPL and SMPL(PD), perform the inqraid command. Check whether or not the volume
is used by XP Business Copy. If the volume is used by XP Business Copy, the volume status is
SMPL(PD). If the volume is not used by XP Business Copy, the volume status is SMPL.
• After an XP Business Copy pair is deleted, to execute a command to perform tasks such as
pair operation or event waiting, wait at least 10 seconds, until the volume status changes from
SMPL(PD) to SMPL. If you do not wait, the command might end abnormally.
Pair Status
Figure 8 (page 20) illustrates the XP Business Copy pair status transitions and the relationship
between the pair status and the XP Business Copy operations.
Pair Status 19