Determining superfluous log files - linear logging only

For circular logging, never delete data from the log directory. When managing linear log files, it is important to be sure which files can be deleted or archived. This information will assist you in making this decision.

Do not use the file system's modification times to determine "older" log files. Use only the log file number. The queue manager's use of log files follows complex rules, including pre-allocation and formatting of log files before they are needed. We might see log files with modification times that would be misleading if you try to use these times to determine relative age.

• The DISPLAY QMSTATUS command
• Logger event messages and, finally
• Error log messages

For the DISPLAY QMSTATUS command, to determine the oldest log extent needed to:

• Restart the queue manager, issue the command DISPLAY QMSTATUS RECLOG.
• Perform media recovery, issue the command DISPLAY QMSTATUS MEDIALOG.
• Determine the name for archive notification, issue the command DISPLAY QMSTATUS ARCHLOG.

We can reduce the number of secondary log extents when using circular logging by issuing the command RESET QMGR TYPE(REDUCELOG).

In general a lower log file number implies an older log. Unless you have a very high log file turnover, of the order of 3000 log files per day for 10 years, we do not need to cater for the number wrapping at 9 999 999. In this case, we can archive any log file with a number less than the RECLOG value, and we can delete any log file with a number less than both the RECLOG and MEDIALOG values.