Managing coupling facility resources provides considerations for setting up a CFRM policy. You format the couple data set that will contain the CFRM policy with the IXCLIDSU utility program. You set up your CFRM policy using the administrative data utility (IXCMIAPU), which resides in SYS1.MIGLIB. See Administrative data utility.

When formatting the couple data set to contain the CFRM policy data, ensure that the value you specify for MAXSYSTEM matches the value for MAXSYSTEM that was used when the sysplex couple data set was formatted.

When coupling facility structures are used for XCF signaling and the MAXSYSTEM value specified for the CFRM couple data set is less than that of the sysplex couple data set, systems might not be able to join the sysplex. For example, if the only signaling connectivity is through coupling facility structures, MAXSYSTEM=16 is specified for the sysplex couple data set, and MAXSYSTEM=8 is specified for the CFRM couple data set, then at most eight systems will be allowed in the sysplex. (The limit might be less than eight, as described in section Implications of the MAXSYSTEM value for the sysplex couple data set.)

In the CFRM policy, you specify the name of the list structure, its size, and a preference list (a prioritized list of the coupling facilities on which you want the list structure allocated). Optionally, you can also specify an exclusion list — the names of any list structures you do not want allocated on the coupling facility the specified list structure is actually allocated on.