NMAP Security Scanner on Linux

First of all, you should get the “nmap” package installed in your system.

On CentOS

yum install nmap

On Debian

apt-get install nmap

On Ubuntu

sudo apt-get install nmap

NMAP Commands:

sudo nmap -sS [IP address] or [website address]

sudo nmap -O --osscan-guess [IP address] or [website address]

sudo nmap -vv [IP address] or [website address]

sudo nmap -sV [IP address] or [website address]

nmap -sn 192.168.1.0/24 or nmap -sP 192.168.1.0/24

Zenmap – A GUI for Nmap

All the above is good and you can dive deeper trying out various options and see what you can learn about a target, but for those that want a more user-friendly approach they should install the “zenmap” package that is a GUI tool for Nmap.

Besides the fact that Zenmap offers convenient boxes to insert your target’s IP (or website address) and outputs results in a more eye-pleasing way and with proper highlighting, its main advantage is the fact that it offers pre-set Nmap commands that you can quickly select and run. Moreover, the software offers a test comparison tool, a topology plotter, and the ability to save scans for administrator review and evaluation.

Scanning Network

nmap -sP 192.168.2.1/24