Hitachi ShadowImage for z/OS user guide (HIT9503-96004, June 2006)
ShadowImage for z/OS user guide 15
• Auto LUN XP
IBM PPRC Host Software Functions
SI390 supports the IBM PPRC host software functions, including TSO PPRC commands and ICKDSF
PPRCOPY commands. SI390 pairs can be added, split, resynced, and deleted using TSO PPRC or ICKDSF
PPRCOPY commands. ”Using PPRC Commands for ShadowImage” on page 71 describes and provides
instructions for using PPRC commands to create and maintain SI390 volume pairs on the
XP1024/XP128/XP12000/XP10000. Also, ShadowImage - FlashCopy® supports the IBM TSO PPRC
commands and DFSMSdss commands. ShadowImage - FlashCopy pairs can be established by defining
“relationship” using TSO PPRC or DFSMSdss commands. ”Using ShadowImage - FlashCopy” on page 85
describes and provides instructions for using TSOPPRC and DFSMSdss commands to ShadowImage -
FlashCopy define relationship.
ShadowImage Requirements
SI390 operations provide disk array-internal copies of S/390 logical volume images (LVIs) on the
XP1024/XP128/XP12000/XP10000. The following table lists and describes the operational requirements
for ShadowImage for z/OS®.
Table 2 ShadowImage for z/OS requirements
Parameter Specification
Pair objects Logical devices (LDEVs): M/F and multiplatform devices that are supported by
XP1024/XP128/XP12000/XP10000, including custom-size devices of Virtual LVI.
Devices must be installed and formatted. The S-VOL and T-VOL must be same type
and same size. For example, 3390-3R to 3390-3R is allowed, but 3380-K to
3390-9 is not allowed. A custom-size S-VOL must be paired with a T-VOL of the
same type and same size. A combination of M/F and multiplatform devices for
creating an SI390 pair is supported. Open volumes (for example, OPEN-3,
OPEN-9, or OPEN-E) are not supported.
Volumes specified as Universal Replicator for Mainframe data volumes or journal
volumes cannot be specified as S-VOLs or T-VOLs.
Available volume ShadowImage for z/OS® can use the volume whose CU:LDEV (control unit image:
logical device ID) is between 00:00 and 3F:FF.
Number of copies Maximum three copies (T-VOLs) per source volume (S-VOL).
Maximum number of pairs The total number of SI390, Business Copy (BC) XP, Snapshot XP, and Auto LUN XP
volume pairs. For details, refer to ”Requirements on the Maximum Number of Pairs”
on page 16.
Maximum number of
reserved volumes
4,096 reserved volumes per XP1024/XP128/XP12000/XP10000.
Combinations of RAID levels All combinations supported: RAID1-RAID1, RAID5-RAID5, RAID1-RAID5,
RAID5-RAID1, RAID6-RAID6, RAID1-RAID6, RAID5-RAID-6, RAID6-RAID1, and
RAID6-RAID5.
Dynamic sparing and auto
correction copy
If a failure occurs that requires use of dynamic sparing or automatic correction
copy, the status of the paired volumes associated with the failed physical device will
not be affected.
Physical device (PDEV)
maintenance
If a PDEV requires maintenance, the status of the logical volumes associated with
that PDEV will not be affected. However, if PDEV maintenance requires access to a
ShadowImage for z/OS pair volume, the pair must be deleted, and the
Reserve
attribute must be reset (unreserved).
Logical device maintenance
LDEV maintenance cannot be performed on LDEVs that are assigned to
ShadowImage for z/OS pairs. If LDEV maintenance requires access to a
ShadowImage for z/OS LDEV, the pair must be deleted, and the
Reserve attribute
must be reset (unreserved).