Change Linux (Ubuntu) Hostname Permanently

1) Modify /etc/cloud/cloud/cfg to allow persistent name change.

sudo nano /etc/cloud/cloud.cfg

Set ‘preserve_hostname’ to ‘true’

preserve_hostname: true

2) Use the hostnamectl command to change the hostname

sudo hostnamectl set-hostname <new hostname>

3) Change /etc/hosts file

127.0.0.1 <new hostname>

4) Add hostname to /etc/hostname

<new hostname>

5) Reboot