MVSSERV supplies diagnostic information that can be put into a TSO/E trace data set. Your system programmer must first allocate this trace data set and give you its name.

By specifying the TRACE or IOTRACE parameters on the MVSSERV command, you can indicate whether you want some or all diagnostic information in the trace data set. If you specify the TRACE parameter, the trace data set includes informational and error messages, an execution path table that tracks module calls, and the requests and replies sent between the PC and the host. If you specify the IOTRACE parameter, the trace data set includes all TRACE output plus I/O related information such as transmission data and the structured fields associated with the data. If you do not specify a parameter, the default is NOTRACE and you get no diagnostic information.