HP XP P9000 Continuous Access Synchronous for Mainframe Systems User Guide

7. I/Os are queued at the host.
8. Host operations are switched to secondary site.
Command sequence example
You can issue CGROUP FREEZE/RUN commands manually or through automation (such as with
GDPS). The following is an example sequence of actions you may implement.
1. Suspend host updates to all P-VOLs on the specified MCU.
2. Block the specified MCU-RCU path to stop update copy operations to S-VOLs.
If the specified MCU does not have any P-VOLs, the FREEZE command is run without performing
any operations (paths are not blocked, SCP is not indicated).
3. Change all P-VOLs to Suspended status.
4. Resume host updates to suspended P-VOLs.
5. Run the add RCU operation to reestablish the blocked logical paths. After logical MCU-RCU
paths are established, make sure to specify the desired SCP time for the MCU using the Remote
Web Console CU Option dialog box. The range for SCP time is 0 to 518,400 seconds (144
hours); the default is 120 seconds.
NOTE: If your specified SCP time is 601 seconds or longer, the microcode version cannot
be downgraded to 70-03-xx-xx/xx or earlier. In this case, lower the SCP time setting to 600
seconds or less, downgrade, then reset to the desired time.
6. After the path is reestablished, run the resynchronize pair operation.
Other TSO commands used with CGROUP
You can use the following TSO commands in your CGROUP FREEZE/RUN workflow:
• Use CESTPATH to recover a blocked MCU-RCU path. Make sure to use the same parameters
as when the path was established.
• After reestablishing the MCU-RCU path that was blocked, use CESTPAIR/RESYNC to
resynchronize the Cnt Ac-S Z pairs suspended by CGROUP/FREEZE.
• After reestablishing the MCU-RCU path that was blocked, use CDELPAIR to release the pairs
suspended by CGROUP/FREEZE. If CDELPAIR is issued to a pair whose MCU-RCU path is
still blocked, the MCU rejects the command (F/M=0F, Cnt Ac-S Z reason code=5A).
• Use CRECOVER to change a suspended S-VOL to simplex. This command is issued to the S-VOL
and does not affect the suspended P-VOL.
• Use CQUERY to generate output about paths and volumes after running CGROUP FREEZE/RUN.
See the next section for examples.
Example output for CQUERY
The following examples show output for CQUERY - PATHS/VOLUMES after CGROUP FREEZE
has run. Output is for illustration only and should not be used.
CQUERY - PATHS
The following figure shows example output when CQUERY is issued to an MCU to which
CGROUP/FREEZE was issued.
118 Pair operations using PPRC