You can create a TrueCopy pair by specifying a DP-VOL (Dynamic Provisioning virtual volume). DP-VOLs can be assigned to both the TC P-VOL and S-VOL, or to one of them. However, the following restrictions apply:
- DP-VOL use is limited by emulation type, as indicated in the following table.
P-VOL
S-VOL
DP-VOL/3390-A
Ordinary volume/3390-A
Ordinary volume/3390-X1, 2
DP-VOL/3390-A
Yes
Yes
No
Ordinary volume/3390-A
Yes
Yes
No
Ordinary volume/3390-X1
Yes
Yes
Yes
Notes:
- 3390 series other than 3390-A.
- DP-VOL use in other than the 3390 series emulation type is not supported for TrueCopy for Mainframe.
- Migrating existing data to DP-VOL/3390-A or ordinary volume/3390-A, DP-VOL 3390-X P-VOL, DP-VOL/3390-A S-VOL, and ordinary volume/3390-A configurations are supported. Swapping to DP-VOL/3390-A or ordinary volume/3390-A P-VOL, and to ordinary volume/3390-X S-VOL is not supported.
- You can use DP-VOLs that are also used in a ShadowImage for Mainframe or Compatible FlashCopy® V2 pair, or in a Volume Migration pair. Before creating the TC pair, delete the SIz or Compatible FlashCopy® V2 pair, or disable the Volume Migration setting. After the pair is created, re-create the pair or migration plan. Note: This is necessary only if both TCz pair volumes are DP-VOLs.
- When a
DP-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
DP-VOL. Therefore, before creating the pair, make sure of the following:
- DP-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:
If a pair does not include a DP-VOL, volume capacity is counted toward TCz license capacity.
If a pair includes a DP-VOL, only the allocated page capacity of volume capacity is counted toward TCz license capacity.
If a DP-VOL and a non-DP-VOL are included in a pair, the page capacity and/or license capacity counted in the P-VOL and the S-VOL might be different. This applies even when both P-VOL and S-VOL include DP-VOLs, because the page capacity of the P-VOL or the S-VOL changes by a released page or other action.
For more information, see the Provisioning Guide for your storage system.