What do I do if my Linux Server / Workstation does not boot?

Q. I’m using Debian Linux and CentOS operating system. My question is what do I do if my server refused to boot? How do I troubleshoot the problem?

A. Usually most Linux distribution provides rescue mode. It allows to access to disk partition and you are allowed to solve the problem.

To use the rescue mode of the install CD, follow these steps:
a) Boot from 1st CD / DVD media

b) Enter rescue at the prompt. (use ‘dd rescue‘ if you need to load the SCSI driver)

c) You will get at a shell prompt. Now you can reinstall boot loader or check disk for errors and so on.

Please note that Linux distributions such as Mandriva or Ubuntu Linux offers menu based troubleshooting options.