The VMS System Event File

This document details the VMS Operating System's System Event File, ERRLOG.SYS, which logs significant system events occurring during operation. Located in the SYSSSYSROOT:[SYSERR] directory, this file records various event types, including device errors, machine checks, system starts, and software parameters, listed in Table 1. Each event triggers a special routine that gathers system status and hardware/software register information before appending it to the ERRLOG.SYS file.

The primary utility for interpreting these binary event logs is ANALYZE/ERRORLOG (and RETRIEVE, a Spear Library function), which uses the Error Log Formatter (ERF) to translate raw data into ASCII reports. The document extensively outlines the numerous command qualifiers for ANALYZE/ERRORLOG, enabling users to precisely filter, format, and generate diverse reports. Qualifiers allow for:

• Selection: specifying time ranges (/BEFORE, /SINCE), entry codes (/ENTRY), specific device classes, names, or event types (/INCLUDE, /EXCLUDE), or CPU System IDs (/SID_REGISTER).
• Output Format: generating full (/FULL), brief (/BRIEF), or binary (/BINARY) reports, saving output to files (/OUTPUT), or extracting cryptic register dumps (/REGISTER_DUMP).
• Summaries: producing statistical reports (/STATISTICS) showing CPU time, page faults, and I/O, or various summary reports (/SUMMARY) including device rollups, event histograms, memory errors, and volume labels.

The document concludes with multiple examples demonstrating the use of these qualifiers and the resulting report formats for various event types, such as Machine Checks, Soft ECC Errors, Environmental Monitor exceptions, and System Bugchecks.