Change Hostname in Linux

Check current hostname

hostname

Temporary change hostname

hostname NEW_HOSTNAME

This will change the hostname for the current session only. Hostname will be reset to the original one after reboot.

Permanent change hostname

Use hostnamectl to change the hostname, this will change the hostname in /etc/hostname file and take effect immediately without reboot.

sudo hostnamectl set-hostname NEW_HOSTNAME && sudo systemctl restart systemd-hostnamed

However, you still need to manually update /etc/hosts file

sudo nano /etc/hosts

Replace any OLD_HOSTNAME with NEW_HOSTNAME, new line should look like this:

127.0.0.1 localhost
127.0.1.1 NEW_HOSTNAME