The Nmap utility will scan devices connected to your network. Nmap is a free open-source utility used by network admins and anyone to explore, scan, secure and audit the network. For example, if your internal network is 10.10.10.0/24 network, you can use the following Nmap options to scan your network.
nmap -sP 10.10.10.0/24
The command above produces the following output:
As you can see, the nmap utility has found 8 devices connected to my network. It usually takes 30 seconds or so to scan the entire network. With the available data, I can now ping, ssh, or view the device via web browser if that service is available. Nmap makes troubleshooting the network that much more easier.
Just like most Linux utilities, nmap has a ton of options worth checking. Simply type
-- help to read more options.
If you are a Windows user, the nmap utility is available for download.
For Ubuntu users, simply type the following to install
sudo apt-get install nmap