nmap - Network exploration tool and security / port scanner.
Scan a server using hostname:
nmap server.your-site.com
Scan a server using IP address:
nmap 192.168.0.1
Scan a server showing detailed information:
nmap -v 192.168.0.1
Scan multiple servers:
nmap 192.168.0.1 192.168.0.2 192.168.0.3
nmap 192.168.0.1,2,3
Scan an IP Address Range:
nmap 192.168.0.1-10
Scan a whole subnet:
nmap 192.168.0.*
Scan a whole subnet excluding some hosts:
nmap 192.168.0.* --exclude 192.168.0.5
Scan servers from a text file:
nmap -iL server-list.txt
Scan OS information and traceroute:
nmap -A 192.168.0.1
Enable OS detection with nmap:
nmap -O server.your-site.com
Scan a host to detect firewall:
nmap -sA 192.168.0.1
Scan online hosts in a network:
nmap -sP 192.168.0.*
Scan host in fast mode:
nmap -F 192.168.0.1
Scan ports consecutively:
nmap -r 192.168.0.1
Print host interfaces and routes:
nmap --iflist
Scan for specific port:
nmap -p 80 server.your-site.com
Scan a specific TCP port:
nmap -p T:80 server.your-site.com
Scan a specific UDP port:
nmap -p U:53 server.your-site.com
Scan multiple ports:
nmap -p 80,443 192.168.0.1
Scan ports range:
nmap -p 80-160 192.168.0.1
Scan host services version numbers:
nmap -sV 192.168.0.1
Scan remote hosts using TCP ACK (PA) and TCP Syn (PS):
nmap -PS 192.168.0.1
Scan remote host for specific ports with TCP ACK:
nmap -PA -p 22,80 192.168.0.1
Scan remote host for specific ports with TCP Syn:
nmap -PS -p 22,80 192.168.0.1
Scan in stealthy mode:
nmap -sS 192.168.0.1
Check most commonly used Ports with TCP Syn:
nmap -sT 192.168.0.1
Perform a tcp null scan to fool a firewall:
nmap -sN 192.168.0.1
Find nmap version:
nmap -V