Finding the ip address of another computer on the network?

Is there a program which can tell me the ip address of a computer when is connected to my network? A list of names or ip addresses.

For example when my wife is on my main desktop computer I can either go on another desktop or laptop and work. However I don't know the ip address of the computer she's on it's dhcp and no static ip addresses. I would like to ssh into the main desktop and work on it. Sometimes I have asked her if I could get on for a minute to get the ip address. From a terminal I do an ifconfig and get the address. I could get it from the router too but that is requires logging into the router. There must be some short command I can run? All the computers are running Ubuntu and samba is not installed. Once I know the ip address I can ssh into the main desktop.

Solution 1:

you could try nmap, if you don't have it, it can be installed via the following :-

sudo apt-get install nmap

you can then scan your network by issuing :-

nmap -sP 192.168.1.0/24

obviously change address range if your network differs

Solution 2:

Modern releases of Ubuntu use avahi, so one could also use avahi-discover

sudo apt-get install avahi-discover

and run with:

avahi-discover

this allows you to view all the machines on the network and see the IP address, MAC address and services running on these machines.

Alternatively one could use:

avahi-browse -rat