An XCF group is a set of related members that a multisystem application defines to XCF. A member is a specific function, or instance, of the application. A member resides on one system and can communicate with other members of the same group across the sysplex.

Communication between group members on different systems occurs over the signaling paths that connect the systems; on the same system, communication between group members occurs through local signaling services.

To prevent multisystem applications from interfering with one another, each XCF group name in the sysplex must be unique.

A multisystem application can use XCF group services (a set of authorized assembler macros) to obtain information about groups and members, define its group members to the sysplex, disassociate members from XCF services, and so forth. For more information about these macros, see z/OS MVS Programming: Sysplex Services Guide.