Error log analysis does not test the resource. Instead this method searches the AIX error log for an entry (or entries) related to the resource. If an entry is found, then an analysis is performed on the error that was logged, and a determination is made by the Diagnostic Application as to whether the resource should be called out as being bad.
Error log analysis is performed via different methods with the Diagnostic Subsystem. One method is that error log analysis is performed automatically whenever an permanent hardware error is logged to the AIX error log. This method is called Automatic Error Log Analysis (DIAGELA).
A second method can be set up to run diagnostics automatically at a pre-set time of the day. This method is referred to as Periodic Diagnostics.
A third method can be run directly from the command line by using the -e flag with the diag command.
A fourth method is invoked automatically whenever diagnostics is ran in Problem Determination Mode after first starting diagnostics. This method is described below.
If Problem Determination mode is selected upon entering diagnostics the first time, the Diagnostic Controller searches the AIX error log for any Permanent Hardware errors. If any errors were logged within the last 24 hours, the appropriate Diagnostic Application is called to analyze the error log. If an problem is suspected due to an error logged, a Problem Report screen will be presented to the user. If no problem is found, then the Resource Selection menu is displayed.