Optional parameters

FREEZE

Specifies that PPRC stop all updates to secondary subsystems for pairs that have primary and secondary volumes on the primary and secondary logical subsystems identified in the CGROUP command. The system suspends these pairs and all paths between the identified primary and secondary subsystems removes.

Use the following guidelines; all host application I/O to the primary is held off with a long busy condition for two minutes, or until a CGROUP command is issued with the RUN option.

Establish the path with CGROUP(YES) specified in the CESTPATH command.
Establish the paths with CGROUP(YES) specified in the copy services GUI or CLI when the consistency group runs.

If you do not specify CGROUP(YES) in the CESTPATH command, the host I/O is not held off with a long busy condition.

To resume operations you must re-establish the paths between the primary and secondary subsystems, and then re-establish the pairs using the MODE(RESYNC) parameter.

To use FREEZE for the consistency of all volumes in a group after an error, use the following process:

Specify CESTPATH command with CGROUP(YES) when establishing paths carrying data for the group.
Use CGROUP with FREEZE on all affected primary to secondary LSS pairs.
Use CGROUP with FREEZE on all affected primary to secondary LSS pairs before the control unit timer has elapsed.

Note:

PPRC does not allow any activity to the secondary volumes.
You cannot specify the FREEZE parameter with the RUN parameter.
Issue all the FREEZE commands before issuing the RUN commands.

RUN

Specifies that host application I/O may resume on primary volumes for pairs which have primary and secondary volumes on the primary and secondary logical subsystems identified in the CGROUP command which have been suspended due to an earlier CGROUP FREEZE command. The pairs remain suspended. You cannot specify the RUN parameter with the FREEZE parameter.

SUBCHSET

Specifies the subchannel set in which the command is to be issued. The subchannel set where the I/O will be issued is the subchannel set as defined in the Hardware Configuration Dialog (HCD). The valid values are determined by what is supported by the host system's processor and configured for the device.

If you omit the parameter, the command is issued to the device that is logically in subchannel set 0. If a swap has occurred, this could be the device that was defined in an alternate subchannel set in the I/O configuration (IODF), with HCD.