You can upgrade a DASD-only log stream to use coupling facility storage, making it a coupling facility log stream, or you can upgrade an existing structure-based log stream to use a different coupling facility structure. To upgrade to a structure-based log stream, associate the structure with the log stream by updating the log stream definition in the LOGR policy. Use the UPDATE request on either the IXGINVNT service or the IXCMIAPU utility to specify the name of the coupling facility structue with the STRUCTNAME parameter. All connectors to either the DASD-only log stream or the existing structure-based log stream being upgraded must be disconnected in order to make the upgrade. No failed or active connections can exist for the log stream.
When updating an existing log stream configuration, the GROUP attribute must be taken into account.
For details about updating the GROUP parameter, see "Parameters for REQUEST=UPDATE" under the topic of IXGINVNT in z/OS MVS Programming: Assembler Services Reference IAR-XCT.
For examples of log stream configuration changes, see Upgrading an existing log stream configuration in z/OS MVS Setting Up a Sysplex.