Nmap help needed (Port Scaning)

General Discussion
1

Hi everyone.
Is there any good way to scan all the ports (65,535) of a server when the server is behind a firewall? I have tried with nmap -p 20-65535 -Pn -F 192.168.1.1

2

Not sure but you can try it…

nmap -sU -sT -p 20-65535 -Pn 192.168.1.0