HP P9000 Continuous Access Synchronous for Mainframe Systems User Guide (AV400-96398, October 2011)

Figure 12 Overview of GDPS operations
Figure key:
1. Read/write I/Os are issued from the host.
2. A failure occurs on a Continuous Access Synchronous Z 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.
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 reestablish the MCU RCU path that was blocked, you can use the
CESTPAIR/RESYNC command to resynchronize the Continuous Access Synchronous Z pairs
suspended by the CGROUP/RUN command.
CDELPAIR: After you reestablish the MCU RCU path that was blocked, you can use the CDELPAIR
command to release the Continuous Access Synchronous Z pairs suspended by the
CGROUP/FREEZE command. If CDELPAIR is issued to a Continuous Access Synchronous Z pair
whose MCU RCU path is still blocked, the MCU rejects the command (F/M=0F, Continuous Access
Synchronous Z 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: Figure 13 (page 92) show the output of the CQUERY command issued to a
Continuous Access Synchronous Z MCU to which the CGROUP/FREEZE command has been issued.
Figure 14 (page 92) shows the output of the CQUERY command issued to the Continuous Access
Synchronous Z RCU that has a blocked path due to the CGROUP/FREEZE command.
CGROUP (FREEZE/RUN) support 91