Problem Solving and Troubleshooting in AIX 5L - IBM Redbooks

Symptom Possible cause Refer to
Core dump error log
entries
Machine fails to boot Hardware or
software
Corrupt boot list Corrupt boot list,
erased boot list, or
list non-existent
device
3 Digit LED starting
0c
1.3 Avoiding problems
The Reliability, Availability, and Serviceability (RAS) features of AIX are
designed to fulfill many functions. As well as helping you determine the cause of
a problem once it has actually occurred, such as the diagnostics subsystem,
many of the RAS features are designed to provide information on potential
problems before they occur. By default, IBM ^ pSeries and RS/6000
systems are configured to run periodic automatic diagnostic checks. Any errors
or warnings reported by this system will appear in the system error log.
Good system administration is not only fixing problems when they occur, but
managing a system in such a way as to minimize the chances of a problem
having an impact on the users of the system.
Periodic system maintenance can help reduce the number of problems
experienced on a machine. Simple tasks, such as cleaning the tape drive as
required, can prevent tape errors. Examining the system error log on a regular
basis can help you spot a potential problem when the related error log entries are
still warnings rather than errors.
1.3.1 System health check
Software failure Section 2.4, “Finding a core dump” on
page 34
System dump in
progress
Section 1.2.1, “Boot path flowchart” on
page 10
Section 3.3.1, “Failure to locate a boot
image” on page 49
Section 4.4.2, “Dump status codes” on
page 85
The following section lists some simple commands that can be run on a regular
basis to monitor a system. They will help you to become aware of how the
system is operating.
► Use the errpt command to look at a summary error log report. Be on the
lookout for recent additions to the log. Use the errpt -a command to examine
any suspicious detailed error log entries.
Chapter 1. Problem determination introduction 17