Hitachi TrueCopy for IBM z/OS User and Reference Guide (T5211-96001, June 2007)

About TrueCopy for z/OS Operations 2-31
Hitachi Universal Storage Platform V TrueCopy for IBM z/OS User’s Guide
Group Operations
TrueCopy for z/OS Async provides the following group-based operations to
simplify and expedite disaster/failure recovery procedures:
• Group operations at the MCU:
– Suspend all pairs in a consistency group (Group suspend option,
supported by CSUSPEND TSO command).
– Resynchronize all suspended pairs in a consistency group (Group
resynchronize option, supported by the CESTPAIR TSO command with
MODE=RESYNC).
– Release all pairs in a consistency group (Group release option, supported
by CDELPAIR TSO command).
• Group operations at the RCU:
– Suspend all pairs in a consistency group (Group suspend option,
supported by CSUSPEND TSO command).
– Release all suspended pairs in a consistency group except for any
inconsistent pairs (C/T release option, not supported by CDELPAIR,
CDELPAIR cannot be issued to the RCU).
– Release all pairs in a consistency group regardless of their consistency
status (Group release option, not supported by CDELPAIR, CDELPAIR
cannot be issued to the RCU).
TCzA also provides the Error level pair option which is used to trigger
automatic suspension of an entire consistency group. When a TCzA pair is
suspended due to failure (not user-requested), this TCzA pair option
determines whether all pairs in the same consistency group will also be
suspended. If you select the Group error level for a TCzA pair, all pairs in the
same group will be suspended. If you select the Volume error level, only the
affected TCzA pair will be suspended.
Note: The Error level pair option is very important for managing TCzA groups
and planning for disaster recovery. The Group error level should be selected
for all TCzA volumes which are essential to disaster recovery. Suspended TCzA
R-VOLs which have the Volume error level should not be used for disaster
recovery.