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HP XP Racks User Manual

Page 21

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1.

Cnt Ac-J Z restores the journal data that was created before you restored the split time to Cnt
Ac-J Z S-VOLs (BC Z P-VOLs).

NOTE:

If a BC Z pair is suspended due to a failure, the split time and the actual task start

time must be the same in order to restore Cnt Ac-J Z journal data that you created before the
split time to the Cnt Ac-J Z/BC Z volume after the split. The task start time is determined by
the amount of journal data in the journal volume at the time of the split.

For example, if the journal volume contains data that needs one hour to be restored, the
starting time of the split operation delays for an hour.

2.

Cnt Ac-J Z detects restore journal (R-JNL) data with a time stamp later than the registered split
time and suspends R-JNL operations.

3.

The BC Z pair is split.

4.

Cnt Ac-J Z resumes the suspended R-JNL operations.

Requirements, restrictions, and guidelines for using consistency group pair-split with shared BC Z
and Cnt Ac-S Z or Cnt Ac-J Z volumes

You can share BC Z P-VOLs with Cnt Ac-S Z or Cnt Ac-J Z S-VOLs but there are requirements,
restrictions, and guidelines for using consistency group (CG) pair-split in these cases.

Requirements

If you are sharing BC Z P-VOLs with Cnt Ac-S Z or Cnt Ac-J Z S-VOLs, CG pair-split has the following
requirements:

All pair operations must be performed using RAID Manager, BCM, or PPRC commands. This
manual assumes you use BCM.

You must share BC Z P-VOLs with the Cnt Ac-S Z or Cnt Ac-J Z S-VOLs.

The Cnt Ac-S Z or Cnt Ac-J Z S-VOLs that you are sharing with the BC Z CG pairs must have
the same status.

If you are sharing BC Z volumes with Cnt Ac-J Z volumes, the pair status must be the following:

(For Cnt Ac-J Z) “DUPLEX”.

(For BC Z) “DUPLEX” or “PENDING”.

If you are sharing BC Z volumes with Cnt Ac-S Z volumes, the pair status must be the following:

(For Cnt Ac-S Z) “DUPLEX”, “Suspended S-VOL by operator”, or “Suspend/SUSPER”.

(For BC Z) “DUPLEX” or “PENDING”.

Restrictions

If you are sharing BC Z P-VOLs with Cnt Ac-S Z or Cnt Ac-J Z S-VOLs, CG pair-split has the following
restrictions:

You can perform one split operation per BC Z CG.

You can:

Split each Cnt Ac-J Z journal up to three times (equivalent to three BC Z CGs).

Quick Split or Steady Split the pairs.

For more information about the methods you can use to split pairs, see

“Pair splitting

methods” (page 49)

.

Splitting pairs using consistency groups

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