Live host discovery

Types of scans

ARP, ICMP, TCP, and UDP can detect live hosts. Any response from a host is an indication that it is online.

Scan Type

Example Command

ARP Scan

sudo nmap -PR -sn /24

ICMP Echo Scan

sudo nmap -PE -sn /24

ICMP Timestamp Scan

sudo nmap -PP -sn /24

ICMP Address Mask Scan

sudo nmap -PM -sn /24

TCP SYN Ping Scan

sudo nmap -PS22,80,443 -sn /30

TCP ACK Ping Scan

sudo nmap -PA22,80,443 -sn /30

UDP Ping Scan

sudo nmap -PU53,161,162 -sn /30

Options

Option

Purpose

-n

no DNS lookup

-R

reverse-DNS lookup for all hosts

-sn

host discovery only
Last update: 2025-05-12 14:16