Thin provisioning, Cautions – HP XP P9500 Storage User Manual

Page 143

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3.

Wait until the non-suspended 3DC pair completes the resulting update and is in DUPLEX status.

4.

Resynchronize the suspended 3DC pair.

Cautions

If Cnt Ac-S Z interoperates with FC Z, specify Track as the unit of storage for the differential
data of the Cnt Ac-S Z pair.

If Cnt Ac-S Z interoperates with FC Z, create the Cnt Ac-S Z pair without using the Cnt Ac-S
Z consistency group function.

The data copied to the Cnt Ac-S Z P-VOL or Cnt Ac-J Z P-VOL by FC Z is asynchronously copied
with the initial copy operation to the Cnt Ac-S Z S-VOL or Cnt Ac-J Z S-VOL. Based on the
speed of the data copy to Cnt Ac-S Z S-VOL or Cnt Ac-J Z S-VOL, the concordance rate of the
Cnt Ac-S Z pair and Cnt Ac-J Z pair is calculated. Based on the copy processing performing
order of the FC Z relationship, initial copy processing of the Cnt Ac-S Z pair, and initial copy
processing of the Cnt Ac-J Z pair, performing of the Cnt Ac-S Z or Cnt Ac-J Z initial copy
operation may be forced to wait. In this case, the concordance speed of the Cnt Ac-S Z or
Cnt Ac-J Z pair may slow.

If the delta resync operation interoperates with FC Z, use the delta resync operation function,
which is supported for the remote command device function.

The relationship with FC Z can be created in the status under which the Cnt Ac-S Z initial copy
operation can be performed. If the P-VOL of the Cnt Ac-S Z pair in the status of Duplex or
Pending Duplex is assigned to the T-VOL of the relationship with FC Z, the initial copy operation
of Cnt Ac-S Z is performed. However, if the relationship of FC Z is created in the status under
which the Cnt Ac-S Z initial copy operation cannot be performed, the Cnt Ac-S Z pair may
be suspended.

Thin Provisioning

THP V-VOLs can be used for either the Cnt Ac-J Z P-VOL or S-VOL, or both P-VOL and S-VOL.

Only Cnt Ac-J Z pair volumes of volume type 3390-A can be used as a THP V-VOL.

THP V-VOLs cannot be used for Cnt Ac-J Z journal volumes.

When a THP V-VOL is used for a Cnt Ac-J Z P-VOL or S-VOL, the Cnt Ac-J Z of the allocated
pages for the THP V-VOL is included in the Cnt Ac-J Z licensed capacity. If the actual licensed
capacity exceeds the available licensed capacity, you may use Cnt Ac-J Z for 30 days. After
30 days, Cnt Ac-J Z pairs may only be split or released.

When specifying a THP V-VOL that has allocated pages to a Cnt Ac-J Z S-VOL, be aware that
used pool capacity will become temporarily larger than the actual capacity, because pages
must be reallocated in the THP V-VOL. Therefore, before creating the pair:

Make sure that THP V-VOL pool capacity is sufficient.

Make sure that the pool-VOLs, which are added to a pool, are not blocked. If the
pool-VOLs are blocked, restore the volume status and then create the pair.

You can use THP V-VOLs that are also used by Business Copy Z or that are in a Auto LUN
migration plan. To do so, proceed as follows:
1.

Delete the Business Copy Z pair and disable the Auto LUN setting.

2.

Create the Cnt Ac-J Z pair.

3.

Re-create the Business Copy Z pair and the Auto LUN migration plan.

Be aware that when a THP V-VOL is used as the Cnt Ac-J Z S-VOL, you might not be able to
update the Cnt Ac-J Z S-VOL because the capacity of the pool-VOL is full. In this instance, pair
status changes to Suspend.

You can reclaim zero pages of the THP V-VOL to release the appropriate pages. Free pool
capacity increases after zero pages are reclaimed, but pages to which the control cylinders

Thin Provisioning

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