How to easily change the hostname on your Ubuntu VPS server, this will work with Ubuntu 16.04, 18.04, 19.10 and 20.04.
hostnamectl to view the system hostname and id related information
Here you can see that aus is my hostname.
Changing the hostname
To change a servers system hostname in Ubuntu 18 or the like use:
sudo hostnamectl set-hostname NEWHOSTNAME
Where NEWHOSTNAME will be the new set hostname.
Next edit the hosts file by running:
sudo nano /etc/hosts
You want to change the old hostname to the new one OR set the new hostname to the correct ipv4.
127.0.0.1 localhost 144.XX.XXX.XX hostnamehere
Note 144.XX.XXX.XX has been edited from the real ipv4 address.
Shift + x and then press
y to save this new configuration.
hostnamectl again to check that the hostname change was successful.