Examining Log Files
Where are the log files? What log file should I be looking at? This is a very active server, are there programs for monitoring all these files?
Applicable to Centos Versions:
- Centos 5.x
Understanding
Explanation of requirements.
- Most log files are located in /var/log/*
- Log analysis and reporting tools
Doing the Work
Basic description of what will be done and what is expected.
- Looking for recent MTA (Mail Transport Agent) messages that could help us:
- Looking for recent HTTPD (Apache) error logs for reasons why we cannot view our website:
- Checking for recent ssh activity:
tail -f /var/log/maillog
tail -f /var/log/httpd/mysite.com-error_log
tail -f /var/log/secure
last|lastb - These commands will show you the last successful logins via ssh (last) or the last
successful attempts including the unsuccessful attempts (lastb).
Troubleshooting
How to test
Explanation troubleshooting basics and expectations.
- Explanation of test step 1:
- Explanation of test step 2:
Test command
Test command or expected output
Common problems and fixes
Describe common problems here, include links to known common problems if on another site
More Information
Any additional information or notes.
Disclaimer
We test this stuff on our own machines, really we do. But you may run into problems, if you do, come to #centos on irc.freenode.net
