I based these instructions from: http://askubuntu.com/questions/9540/how-do-i-change-the-computer-name
If, for whatever reason you need to change your hostname, as I had to, you need to edit the computer name in two files:
These will both need administrative access, so run
gksu gedit /path/to/file
Replace any instances of the existing computer name with your new one.
Note: If you don’t have gksu installed, you need to: sudo apt-get install gksu
run sudo service hostname restart or restart your computer and the name will have been changed.
First: The “hostname” command.
You can use the hostname command to see the current host name of the system.
You can also use the hostname command to change the host name of the machine.
# hostname smallhat.putorius.net
Then issue the hostname command again to see the changes.
This only makes a temporary or non-persistent change of hostname.
Second: The /etc/sysconfig/network configuration file. (preferred method)
In order for the change to survive a reboot, or to make it persistent, you must change it in the /etc/sysconfig/network file.
Open the file in your favorite editor and change the following line to reflect your desired hostname.
After making changing to the configuration file you need to restart the network service in order to read that file.