NMAP Guide

Ermm....folow kt bawah utk NMAP guide....

nmap -sS -O -p 20-25 127.0.0.1
-sS= TCP SYN scan
-O = Check jenis sistem operasi
-p = Port range dari 20 hingga 25

nmap -sU 127.0.0.1
-sU = Scan UDPport

Using Nmap GUI

Fedora / CentOS :: sudo yum install nmap nmap-frontend
Ubuntu / Debian :: sudo aptitude install nmapfe

Reference::
OS Detection
Scripting Engine
Port Scanning Basic
NMAP Book Guide
GoTo Linux
Scan Open Port
Linuxjournal