Hitachi Universal Storage Platform VM - Manual (Page 55)

Functional and Operational Characteristics 3-11
Hitachi Universal Storage Platform V/VM User and Reference Guide
Mode Category Function Default MCU/RCU
64
(cont.) TrueCopy for z/OS Mode 64 = OFF (default):
ƒ When receiving the Freeze command, pairs that fulfill the
conditions below are suspended and the SCP is set. In the
case of CU emulation type 2105/2017, the path between
MCU and RCU is deleted, while the path is not deleted but
unusable with Query displayed only in the case of CU
emulation type 3990.
ƒ When receiving the RUN command, the SCP status of the
pairs that fulfill the conditions below is released.
ƒ When a Failure Suspend occurs while the Freeze Option
Enable is set, except the pair in which the Failure Suspend
occurs, other pairs that fulfill the conditions below go into
SCP state.
Conditions:
ƒ TrueCopy Sync M-VOL
ƒ Mainframe Volume
ƒ Pair status: Duplex/Pending
ƒ A pair whose RCU# is identical to the RCU for which the
Freeze command is specified.
Note:
1. General use: Mode 64=Off (default)
2. When all the following conditions are met, set Mode
64=ON.
ƒ Customer requests to stop the update I/O operation to
the RCU of a TrueCopy for z/OS pair for the whole
subsystem.
ƒ Disaster Recovery function such as GDPS, HyperSwap,
or Fail Over/ Fail Back, which requires compatibility with
IBM storage, is not used as this Mode 64 operates
without having compatibility with IBM storage.
ƒ Only Peer-to-Peer-Remote-Copy operation. (Do not use
it in combination with Business Continuity Manager.)
3. Even though the Failover command is not an applicable
criterion, when executing the Failover command while
Mode 114 is ON, since ports are not automatically
switched, the Failover command fails.
4. With increase of Sync pairs in subsystem, the time period
to report the completion of Freeze command and RUN
command gets longer (estimate of time to report
completion: 1 second per 1000 pairs), and MIH may occur.
OFF MCU/RCU
80 ShadowImage for
z/OS Determines whether Quick Restore or Reverse Copy, if not
specified, is performed at the execution of pairresync by CCI.
Mode 80 = ON: Reverse Copy is performed.
Mode 80 = OFF: Quick Restore is performed. OFF –
87 ShadowImage Determines whether NormalCopy or QuickResync, if not
specified, is performed at the execution of pairresync by CCI.
Mode 87 = ON: QuickResync is performed.
Mode 87 = OFF: NormalCopy is performed.
OFF –
93 TrueCopy for z/OS
Async TrueCopy for z/OS Async throttling feature. OFF MCU
104 TrueCopy for z/OS Changing default of CGROUP Freeze option. OFF MCU