Network Services And Ports

NETCAT:

• Test a listening port

nc -vz mail.domain.com 587

NETSTAT:

• List all active TCP and UDP port

netstat -tupanc

• List all TCP ports in listening state

netstat -tl

• List all UDP ports in listening state

netstat -ul

• List all UNIX domain sockets in listening state

 netstat -xl

TRACEROUTE:

traceroute -T mail.domain.com -p 25

NMAP:

• Network Fast Discovery With Nmap

nmap -A -F -T5 192.168.1.200-250