Traceroute to IP address
nmap -sn --traceroute remoteipaddressTraceroute to port
nmap -Pn --traceroute -p 443 remoteipaddressOutput:
PORT STATE SERVICE
443/tcp open https
Open means its ok
PORT STATE SERVICE
443/tcp filtered https
Filtered means that a firewall or some filtering or other network issue is covering the port and preventing nmap from determining if the port is open.
Check if port opened
nmap -p 3306 remoteipaddress