How to debug fedora hanging after upgrading from rh9

[Randy Paries]

Hello,
I have just rebuilt a box that had been running rh9 in a production
env (apache and tomcat) for about 3 years. I just rebuilt it with
fedora 4 ( repartitioned and formatted )

There is nothing in the message log file.

How is the best way to debug this? Are there other log files i can look in?

this is a production box and has been running ok for 2 days and since
6 tonight it has hung 3 times. I go to the console and there is
nothing and it is completely hung

Thanks for any help

Randy