HP XP7 Storage - Manual (Page 52)

Used as S-VOL? Used as P-VOL? Functions and volumes
Yes. If the volume is disabled
for use as S-VOL, the volume
cannot be used as S-VOL. Yes Volume registered in a security group
1. The volume performs differently according to the type of difference management.
2. For more information, contact the HP Technical Support.
3. If you use Cnt Ac-S Z with Compatible FlashCopy, the Cnt Ac-S Z pairs must be created without using the consistency
groups.
4. See the section on compatible software in the HP XP7 for Compatible FlashCopy Mirroring User Guide.
5. When you create Compatible FlashCopy Preserve Mirror relationships in COPY mode, both copies are not
synchronized. If you issue Withdraw during the copy operation, both copies of the relationship are suspended.
Therefore, the consistency of the data between P-VOL and S-VOL is not ensured even though the Cnt Ac-S Z pair is
in Duplex status. To release this status, delete the Cnt Ac-S Z pair.
The following topics include additional information about shared volumes.
Thin Provisioning Z
You can create a Continuous Access Journal pair by specifying a THP V-VOL (Thin Provisioning
virtual volume).Thin Provisioning Z virtual volumes (THP V-VOLs) can be assigned to both the Cnt
Ac-S Z P-VOL and S-VOL, or to one of them. However, the following restrictions apply:
•
THP V-VOL use is limited by emulation type, as indicated in the following table.
S-VOL P-VOL
Ordinary volume/3390-X
1,
2
Ordinary volume/3390-A THP V-VOL/3390-A
No Yes Yes THP V-VOL/3390-A
No Yes Yes Ordinary volume/3390-A
Yes Yes Yes Ordinary volume/3390-X
1
1. 3390 series other than 3390-A
2. THP V-VOL use in other than the 3390 series emulation type is not supported for Continuous Access Synchronous
Z.
•
Data migration is supported from an ordinary volume S-VOL/3390-X to a THP V-VOL/3390-A
S-VOL. However, the swap operation in this case is not supported.
•
You can use THP V-VOLs that are also used in a Business Copy Z or Compatible FlashCopy
pair, or in a Auto LUN migration plan. Before creating the Cnt Ac-S Z pair, delete the BC Z
or Compatible FlashCopy pair, or disable the Auto LUN setting. After the pair is created, then
re-create the pair or migration plan.
•
When a THP V-VOL has pages allocated to an S-VOL, used pool capacity is temporarily larger
than the actual capacity because pages must be reallocated in the THP V-VOL. Therefore,
before creating the pair, make sure of the following:
◦ THP V-VOL pool capacity is sufficient.
◦ Pool-VOLs that are added to a pool are not blocked. If Pool-VOLs are blocked, restore
the volume status and then create the pair.
•
Regarding page and license capacity:
When you create a Cnt Ac-S Z pair with a THP V-VOL, the page capacity allocated to
the THP V-VOL is accumulated on the Cnt Ac-S Z license capacity. However, Thin ◦
52 Sharing Continuous Access Synchronous Z volumes