Hitachi ShadowImage for IBM z/OS User"s Guide (T5213-96002, June 2007)

5-24 Performing ShadowImage for z/OS Operations Using Storage Navigator
Hitachi ShadowImage™ for IBM
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z/OS
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User’s Guide
3. When you specify the copy group, select the split type; Quick Split or
Steady Split.
Note: When you register the split time, the split type will be Quick Split.
4. Perform the pair create operation.
5. Perform the pair split operation on the SIz pairs that are created for At-
Time Split function.
The At-Time Split option is enabled, and data in all S-VOLs in the same
consistency group is created in the corresponding T-VOLs at the time when
the pairsplit request is received by the storage system.
Cautions on executing the At-Time Split function:
– Change the status of pairs in the same consistency group according to
the copy group.
– If you are going to execute the At-Time Split function successively,
before you execute the function for the second time, verify that status
of all the pairs in the same consistency group is changed to the status
which is specified by the YKEWAIT command. For detailed information
about the YKEWAIT command, see the Business Continuity Manager
User’s Guide.
If you do not follow the abovementioned notes, the data in the S-VOL when
the Split operation is performed by the At-Time Split function may not be
copied to the T-VOL.
Notes on registering the split time:
– For the pairs in the consistency group to which you registered the Split
time, you can only perform Suspend Pair operations or Delete Pair
operations. If you perform Add Pair, Split or Pair Resync operation,
registration of the Split time will be rejected. If you want to perform
Add Pair, Split or Pair Resync operation, you must first reset the
registration of the Split time.
– The specified Split time will be reset by switching off the power supply.
– If the Split time is registered, the Split operation is performed at the
time of reception of the read/write request with a time stamp that has
passed the time specified as the Split time. The Split operation may be
delayed in case no read/write request is issued and the Split operation,
as a result, is performed as a result of timeout of the storage system
timer.
– If the Split time is registered, and if there is a pair in the consistency
group that cannot be split completely during the Split operation, the
status of this pair will remain the same as before the Split operation.