Change hostname (temporarily or permanently)

Say our host is called

alpha

and we want to rename it to

bravo

For a temporary change (does not survive reboot) run in a terminal:

(sudo) hostname bravo

For a permanent change, edit

/etc/hosts

find the entry for

alpha

and change it to

bravo

Next, edit

/etc/hostname

and replace

alpha

with

bravo

NOTE:BSD based systems use /etc/HOSTNAME instead!

Lastly, EITHER restart the networking service in a terminal:

(sudo) service networking restart

and log out / log in again, OR reboot the machine.

NOTE: If the machine cannot be rebooted immediately after the

changes, or you do not want to log out of your session until later,

simply run:

(sudo) hostname bravo