How to change system hostname in Ubuntu

Hostname is used to identify a system to the local network. On Ubuntu, system hostname is set during the installation process.

Hostname information is set on /etc/hostname. You can change the hostname of your Ubuntu system at any time after the installation by editing the file or by using hostnamectl command from the terminal.

1. Launch terminal.
2. Check current hostname using hostname command.

   user@host:~$ hostname
   host

3. Set new hostname using hostnamectl.

   user@host:~$ sudo hostnamectl set-hostname newhostname
   [sudo] password for user:

4. Run hostname command again to confirm hostname change.

   user@host:~$ hostname
   newhostname

5. Run a new shell to see the change in shell prompt.

   user@host:~$ bash
   user@newhostname:~$

   This only works if $PS1 is set to display the hostname.