To change the computer name on Ubuntu, be it on your home server or an Ubuntu server in the cloud, you can proceed as follows:

  1. Type the hostnamectl command :
    sudo hostnamectl set-hostname newNameHere
    Delete the old name and setup new name.
  2. Next, edit the /etc/hosts file:
    sudo nano /etc/hosts
    Replace any occurrence of the existing computer name with your new one.
  3. Reboot the system to changes take effect:
    sudo reboot