How to change a hostname

Question

During Debian installation, I set my hostname to the wrong value, and now I would like to correct that.

Answer 1

The hostname is stored in three different files:

• /etc/hostname Used as the hostname
• /etc/hosts Helps resolving the hostname to an IP address
• /etc/mailname Determines the hostname the mail server identifies itself

You might want to have a deeper look with grep -ir hostname /etc

Restarting affected services might be a good idea as well.

Answer 2

The value is stored in /etc/hostname. After modifying, apply it with /etc/init.d/hostname start

Answer 3

Various services may also depend on being able to resolve the hostname locally, which is often handled by an entry in the /etc/hosts file.