Global resource serialization will ignore non-applicable parameters on the GRSDEF statement(s) when initializing systems into a star complex as well as when initializing systems into a ring complex. It is possible for an installation to create a single GRSCNFxx parmlib member that can be used for the initialization of either a star or a ring complex. This will help in the transition from a ring to a star complex if the installation elects to use the SETGRS MODE=STAR capability to make the transition. When ring-related parameters are ignored, global resource serialization will issue message ISG313I indicating the parameter and the reason.

When initializing a system into either a ring or a star complex, syntax or specification errors in the GRSCNFxx parmlib member will, in most cases, result in the initialization failing. The failure might occur whether or not the parameter in error was applicable to the particular type of complex being initialized. In these cases, an error message will always be issued and then if it is possible for system processing to continue without global resource serialization, the operator will be prompted to specify NONE or else re-IPL the system. If it is not possible to continue (for example, PLEXCFG=MULTISYSTEM was specified), then initialization will be terminated with an X'0A3' wait state with reason code X'0C'.

Figure 1 shows an example configuration consisting of a three system sysplex (SYS01, SYS02, and SYS03) and a set of GRSCNFxx parameters that might be used to initialize the systems as a global resource serialization star complex. In this example, the global resource serialization lock structure (ISGLOCK) must have been previously defined to the CFRM policy.

Figure 1. Example Global Resource Serialization Star Parmlib Definition

GRSCNFxx parmlib member:
                              /* SYSTEM DEFINITIONS .........

   GRSDEF MATCHSYS(*)         /* GRSDEF FOR SYSTEMS SYS01 AND SYS02     */
          CTRACE(CTIGRS01)    /* PARMLIB MEMBER CTIGRS01 CONTAINS TRACE */
                              /* OPTIONS                                */

   GRSDEF MATCHSYS(SYS03)     /* GRSDEF FOR SYSTEM SYS03                */

          CTRACE(CTIGRS02)    /* PARMLIB MEMBER CTIGRS02 CONTAINS TRACE */
                              /* OPTIONS                                */