changing hostname in ubuntu

I cloned a virtual server and late realised they had the same hostname.

No problem.

1. change the hostname in /etc/hostname:

sudo nano /etc/hostname

2. change the hostname in /etc/hosts:

this file will contain localhost and your old hostname. eg,

127.0.0.1 localhost
127.0.1.1 <new-host-name>

edit this file to suit.

Finally, change the hostname in the current session:

This can be done one of two ways. Restart the system, or issue the following command:

sudo hostname <new-host-name>