Hitachi TrueCopy for z/OS (T1711-96009, June 2006)

TrueCopy for z/OS user guide 173
1. Read/write I/Os are issued from the host.
2. A failure occurs on a TC390 M-VOL and the MCU suspends the pair.
3. Suspend and extended long busy state are reported to the host.
4. Host reports IEA494I with extended long busy state.
5. CGROUP/FREEZE commands are issued to groups.
6. SCP sense bytes are reported if an I/O is issued to a frozen volume.
7. I/Os are queued at the host.
8. Switch to remote (secondary) site.
Figure 72 Overview of GDPS operations
Using PPRC TSO Commands with CGROUP Support
CESTPATH. You can use the CESTPATH command to recover a blocked MCU-RCU path. Make sure to use
the same parameters as when the path was established.
CESTPAIR. After you re-establish the MCU-RCU path that was blocked, you can use the CESTPAIR/RESYNC
command to resume the TC390 pairs suspended by the CGROUP/RUN command.
CDELPAIR. After you re-establish the MCU-RCU path that was blocked, you can use the CDELPAIR
command to delete the TC390 pairs suspended by the CGROUP/RUN command. If CDELPAIR is issued to
a TC390 pair whose MCU-RCU path is still blocked, the MCU rejects the command (F/M=0F, TC390 error
code=5A).
CRECOVER. You can use the CRECOVER command to change a suspended R-VOL to simplex. This
command is issued to the R-VOL and does not affect the suspended M-VOL.
CQUERY/PATHS. The following example shows the output of the CQUERY command issued to a TC390
MCU to which the CGROUP/FREEZE command has been issued.