Assign a Static IP

To assign a static IP in Ubuntu, modify the file /etc/network/interfaces.

But first, pick an address that is not in the pool used for your DHCP server (probably in your router - the user manual should help you with this). The gateway should be set to the router's internal network address. It is likely that your settings will differ from mine.

Get the current settings

ifconfig eth0 (Note the Mask setting)

Open the file with VI

sudo vi etc/network/interfaces

Find the primary network interface configuration

auto eth0
iface eth0 inet dhcp

Change to the static settings

auto eth0
iface eth0 inet static
address 192.168.254.1
netmask 255.255.255.0
gateway 192.168.254.254

Save the file

Restart the network interface

sudo /etc/init.d/networking restart

Check the interface by pinging your router

ping 192.168.254.254 (use your gateway address here - CTRL-C to stop the ping)

Alternatively, you can ping a public server, such as Google

ping www.google.com

Now that a static IP is assigned, add a line to the hosts file on the client machines to assign a name to the server. (If you are using a local DNS, you're way beyond my level!)

NOTE: I should note that I really hate the editor VI. As soon as learn about another command line editor, I'll never use it again. Until then, I'm using this cheatsheet page of commands.