How to update CentOS 5.3 to CentOS 5.4
CentOS 5.4 was released on 22. Oct 2009
If you wan to update, first verify there are no known problems or version conflicts with your software.
Be sure you have a backup and take a snapshot if your using VMWare or other virtualization technologie.
This will install all new packages. After you have updated your system you need to reboot
Now you have to check that all services will start correctly.
If you're running CentOS at VMWare you need to reinstall the VMWare Tools:
Review all error system messages if there are problems:
tail -f /var/log/messages
For me update worked without problems.