nmap cheatsheet

TCP/SYN port scan (default)

nmap $target -sS

TCP port scan without root

nmap $target -sT

Skip discovery ping

nmap $target -Pn

Ping scan only

nmap $target -sn

Report why port open/closed

nmap $target -reason

Enable OS detection

nmap $target -O

Enable OS detection, version detection, script scanning, traceroute

nmap $target -A

Attempt to determine version of service on a port

nmap $target -sV

Use tiny fragmented IP packets

nmap $target -f

Set custom MTU size

nmap $target -mtu [value]