When an error occurs, the system records information about the error in either the logrec data set or a sysplex-wide logrec log stream. The diagnostic information provides a history of all hardware failures, selected software errors, and selected system conditions.
Use the records in the logrec data set or the logrec log stream as a companion to dump data. The information in the records will point the system programmer in the right direction while supplying symptom data about the failure.
For more information about log streams, see z/OS MVS Programming: Assembler Services Guide. For more information about initializing a logrec data set or setting up a logrec log stream, see z/OS MVS Diagnosis: Tools and Service Aids.