Ubuntu – Set ip address and stuff on Ubuntu

The only thing missing from ifconfig are the gateway and DNS servers.

15.04 and newer

To get the DNS and Gateway info just type:

nmcli dev show eth0

The output lists some device parameters including some IP4.DNS[x] entries, which show the DNS servers and a IP4.ADDRESS[1] line which lists the IP and Gateway used (look for the gw = ???.???.???.??? part at the end of the line up to 15.10). On 16.04 and newer versions there is a IP4.GATEWAY line which is pretty self explanatory.

Replace eth0 with the actual device name you're using, which may not be the same. To get a list of devices and their status type:

nmcli dev status

Up to and including 14.10

You can get these with nm-tool (in Ubuntu versions prior to 15.04) which BTW is the command line version of network manager.

To run it just type in a terminal:

nm-tool

If you're using Ubuntu 15.04 or newer the nm-tool has been replaced by the nmcli command which is different. Check the section called "15.04 and newer" above this one in this case.

Just set the IPs manually using the 'network connection' GUI to, say, 192.168.1.1 on ubuntu 11.04 machine and 192.168.1.2 on ubuntu 12.04 machine. Set the netmask to 255.255.255.0 on both of them. Leave the dns and gateway fields blank (I am assuming you only want each other to talk with no internet). This will work. If you wish to connect just these 2 machines, then there is no need of a switch - directly connect each other with the ethernet cable.
(I assume you know how to create a new connection in ubuntu and set the ip manually.)