This step applies to both the DASD-only and coupling facility log streams.

For each log stream, you must decide whether to define it as DASD-only or coupling facility (see Determine the right kind of log stream for each application). Use the DASDONLY parameter on a DEFINE LOGSTREAM request as follows:

To define a log stream as a coupling facility log stream, specify or default to DASDONLY(NO) on the log stream definition. You must also specify a structure name on the STRUCTNAME parameter in the definition for a coupling facility log stream.

To define a log stream as DASD-only, specify DASDONLY(YES) on the definition for a log stream that is not associated with a coupling facility structure. When you define a DASD-only log stream, you can also specify MAXBUFSIZE on the DEFINE LOGSTREAM request to define the maximum buffer size that can be written to the DASD-only log stream.