Open Port Scanning and OS Detection with Nmap in Kali Linux

In this tutorial we will use Nmap in Kali Linux to look for open ports and use OS detection. Nmap stands for Network Mapper and is an open source network scanning and security control tool that comes bundled with Kali Linux, but it is also available for Windows, OSX and many other UNIX platforms. Nmap also has a graphical user interface called Zenmap.

First I want to start with a little warning: Be careful when using the most aggressive Nmap features against hosts that you do not have or are not allowed to scan. It could be against the terms of your ISP to use some features of Nmap.

 Open Port Scanning and OS Detection

We start with a ping scan in an IP range to determine live hosts.

$ nmap -sP 192.168.0.0-100
$ nmap -sP 192.168.2.1/24

Next, we will start a SYN scan with OS detection on one of the active hosts.

$ nmap -sS [ip address]-O

Now, We will now start a scan of open ports with version detectio.

$ nmap -sV 192.168.0.1 -A

When we add -v to the command we can increase verbosity.

$ nmap -sV 192.168.0.13 -A -v