Coupling Facility Log Streams: If an installation defines DASD staging data sets for a coupling facility log stream, the data sets are created, if necessary, during connection processing for the first IXGCONN request issued against a log stream from a particular system.
DASD-Only Log Stream: For a DASD-only log stream, the staging data set is automatically created during the first connect issued against the log stream. A staging data set is not optional for a DASD-only log stream.