1. First make a backup of the following files.
cp /etc/hosts /etc/hosts.back cp /etc/hostname /etc/hostname.back
2. Edit the ‘hosts’ file:
vi /etc/hosts
The file should look like this:
127.0.0.1 localhost 127.0.1.1 your_new_hostname
Here, change “some_hostname” to the new hostname / computer name.
3. Edit the hostname file:
vi /etc/hostname
This file only contains your hostname so change it again to the new_hostname
4. Now restart the hostname and networking services:
service networking restart
it could be that you will disconnected for a wail. after this re-login and check your new hostname with:
hostname -f
- See more at: http://www.unixmen.com/change-hostname-ubuntu-13-10/#sthash.EYB6bzAf.dpuf