Kernel panic

[Hawki]

I'm using CentOS 5.5 and want to know what is a Kernel panic, how you use it and where would I find it's log file.

 

[Noway2]

Quoting from wikipedia,

A kernel panic is an action taken by an operating system upon detecting an internal fatal error from which it cannot safely recover. The term is largely specific to Unix and Unix-like systems; for Microsoft Windows operating systems the equivalent term is "Bug check" (or, colloquially, "Blue Screen of Death").

I haven't used centos, so I can't say specifically which log file(s) relevant information would be located in. I would look for a kernel log, as well as looking at dmesg, messages, faillog, and debug if you have them (it varies by distribution and how you have configured your system).

In my experience, a kernel panic is mostly associated with device drivers that are either the incorrect version or failure to load a device driver that is required for system operation. An example would be using an EXT4 drive and not loading the EXT4 kernel module which would prevent the system from being able to mount the drive and boot.