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

Preparing for ShadowImage™ for IBM
®
z/OS
®
3-11
Hitachi ShadowImage™ for IBM
®
z/OS
®
User’s Guide
Identifying the Source and Target Volumes
For each volume, write down the CU image and LDEV ID, whether the volume
will be an S-VOL or T-VOL, and the other volume(s) in its pair (see Table 3-4
for a sample table). The S-VOLs will remain fully accessible to all hosts
throughout normal SIz operations (except during reverse copy and quick
restore). The T-VOLs will need to be varied offline before being reserved for
SIz operations. Once assigned to a pair, a T-VOL rejects all write I/Os, except
when the pair is split.
Table 3-4 Sample Table for SIz Configuration Information
CU # LDEV
#
S-
VOL?
Associated T-VOL(s) T-VOL? Associated S-VOL
0 00 Yes 0:10, 0:11 No --
0 01 Yes 0:12, 0:13 No --
etc. … … … … …
0 0F Yes 0:2E, 0:2F No --
0 10 No -- Yes 0:00
0 11 No -- Yes 0:00
0 12 No -- Yes 0:01
etc. … … … … …
Requirements for Maintaining ShadowImage for z/OS
This section describes the requirements for the maintenance of ShadowImage
for z/OS. When the storage system maintenance is performed, or the
microprogram is updated, you may have to add SIz
pairs again. Also note that
if the SIz operations are not completed because of failures, copying process
will be automatically suspended.
Cautions on Maintaining the Devices
• Maintenance of PDEV
The maintenance of a PDEV which is not used by ShadowImage for z/OS
does not affect the SIz operations and the status of SIz pairs. You can
maintain a PDEV which contains LDEVs used by ShadowImage for z/OS
independently of the SIz operations or SIz pair status. Even if a PDEV
failure occurs, SIz
pair status is not affected because of the RAID
architecture.
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.
• Maintenance of LDEV
– If an LDEV failure occurs, the pair is suspended.