Defining a CICS® VR XCF group

In a sysplex environment an instance of the CICS® VR server address space must be installed and running on particular systems.

Each system that:
  • Runs batch jobs that start CICS® VR VSAM batch logging.
  • Notifies CICS® VR about backups created for VSAM spheres.
  • Notifies CICS® VR about CICS® TS backout failures.

Only one instance of CICS® VR can be active for each system.

Various tasks performed by the CICS® VR server address space update the contents of the CICS® VR Recovery Control Data Sets (RCDSs) allocated to the CICS® VR server. The information in the RCDSs is then read by CICS® VR during recovery job construction and processing. Therefore, to ensure data integrity of the RCDSs it might be desirable to logically group the CICS® VR instances.

For example, consider the following scenario:
  • The CICS® VR server address space is installed on 2 systems in a sysplex environment.
  • Both systems run batch jobs that start CICS® VR VSAM batch logging for common VSAM spheres.

In this scenario, if a common VSAM sphere becomes corrupted, the updates made by batch jobs ran on both systems need to be recovered. Therefore, the same RCDSs must be allocated to both of the CICS® VR instances in the sysplex. To enforce usage of the same RCDSs, CICS® VR contains the CICSVR_GRPNAME_SUFFIX() parameter.

CICS® VR allows you to logically group CICS® VR instances into cross-system coupling facility (XCF) groups by specifying the following parameter in the active IGDSMSxx member:
CICSVR_GRPNAME_SUFFIX(suffix)
Where suffix specifies the CICS® VR XCF group name suffix. The suffix can be 1 - 4 characters in length, and can be alphanumeric, A-Z, 0-9, and national ($, @, and #). PROD is the default value.

CICS® VR ensures that all systems defined with the same CICS® VR XCF group name suffix use the same set of RCDSs. Therefore, all CICS® VR instances that either run batch jobs or notify CICS® VR of backups created for common VSAM spheres must use the same CICS® VR XCF group name.

When grouping CICS® VR instances into XCF groups, the following notes must be considered:
  • IBM® recommends that all CICS® VR instances that are part of the same CICS® VR XCF group use common CICS® VR load module libraries, SDWWLOAD and SDWWLPA. This ensures that all CICS® VR instances in a CICS® VR XCF group use the same level of CICS® VR.

    Because CICS® VR XCF groups operate independently of each other, CICS® VR instances defined to a different CICS® VR XCF group can use a different level of CICS® VR.

  • Issuing a SETSMS command to change a CICS® VR parameter only changes the specified parameter on the system that processes the request. The ROUTE command must be used to route the SETSMS command to all relevant systems. Also, some values changed by the SETSMS command only take effect when the system is restarted. Therefore, when updating a CICS® VR parameter on all systems in a CICS® VR XCF group, you must terminate and restart all active CICS® VR servers after issuing the SETSMS command.
  • All CICS® VR instances that perform batch logging or register backups for common VSAM spheres must be grouped into the same CICS® VR XCF group.
  • All CICS® VR instances in a CICS® VR XCF group must have access to the same RCDSs. CICS® VR ensures all instances in a CICS® VR XCF group use the same RCDSs.