HP XP P9500 Storage - Manual (Page 49)

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Reverse Copy. Reverse full resync from S-VOL to P-VOL.
The P-VOL is inaccessible to hosts. ◦
◦ All differential data is updated to the P-VOL.
◦ Pairs sharing the same P-VOL must be in PSUS or PSUE status.
◦ If the pair shares a volume with Cnt Ac-S or Cnt Ac-J, you must suspend the Cnt Ac-S or
Cnt Ac-J pair to perform the Reverse Copy or Quick Restore operation.
◦ You cannot create a Cnt Ac-S or Cnt Ac-J pair with a volume shared by BC during the
Reverse Copy or Quick Restore operation.
◦ When the Reverse Copy or Quick Restore is in progress, you cannot create, split, or
resync any pair sharing the same P-VOL. However, the pairs can be deleted or suspended.
◦ Reverse Copy cannot be used for the following:
- BC L2 pair
- Business Copy Z (BC Z) pair when the P-VOL is shared with an FC Z/FCSE volume
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Quick Restore, P-VOL and S-VOL are swapped. NO data is copied, and the pair is placed in
PAIR status. Differential data is copied to the S-VOL during update copy operations.
◦ Differential data is copied during update copying.
◦ The P-VOL and S-VOL are inaccessible during this operation. When the operation
completes, the P-VOL is accessible.
◦ Pairs sharing the same P-VOL must be in PSUS or PSUE status.
◦ When there is a small amount of differential data between P-VOL and S-VOL, the Reverse
Copy operation may complete faster than the Quick Restore operation.
◦ Performing LDEV maintenance during the Quick Restore process increases the time for
the operation to complete.
◦ If the pair shares a volume with Cnt Ac-S or Cnt Ac-J, you must suspend the Cnt Ac-S or
Cnt Ac-J pair to perform the Reverse Copy or Quick Restore operation.
◦ You cannot create a Cnt Ac-S or Cnt Ac-J pair with a volume shared by BC during the
Reverse Copy or Quick Restore operation.
◦ When the Reverse Copy or Quick Restore operation is in progress, you cannot create,
split, or resync any pair sharing the same P-VOL. However, the pairs can be deleted or
suspended.
◦ Quick Restore cannot be used for the following:
- A BC L2 pair
- When a quick format is being performed on either pair volume
- A pair in which one volume is a THP V-VOL, though not both
- When the BC S-VOL is shared with a FS or SS volume
Prerequisite information for resynchronizing
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For Normal Copy and Quick Resync, the S-VOL must be offline.
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For Reverse Copy and Quick Restore, the P-VOL must be offline.
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For Normal Copy or Quick Resync, the pair must be in PSUS, PSUE, or PSUS(SP)/PSUS status.
Pair resynchronization 49