- Nick Congleton
IntroductionNmap is a powerful tool for discovering information about machines on a network or the Internet. It allows you to probe a machine with packets to detect everything from running services and open ports to the operating system and software versions.
Like other security tools, Nmap should not be misused. Only scan networks and machines that you own or have permission to investigate. Probing other machines could be seen as an attack and be illegal.
That said, Nmap can go a long way in helping to secure your own network. It can also help you to ensure that your servers are properly configured and don't have any open and unsecured ports. It will also report if your firewall is correctly filtering ports that should not be externally accessible.
Nmap is installed by default on Kali Linux, so you can just open it up and get started.