Jul 08, 2020

Oct 10, 2018 How to Check If FTP Port 21 Is Not Blocked Jun 16, 2020 How to check if a port is allowed in iptables? Oct 10, 2017 linux - How to check whether port 25 is open or blocked You can use nmap -sT localhost to determine which ports are listening for TCP connections from the network. To check for UDP ports, you should use -sU option. To check for port 25, you can easily use nmap -p25 localhost. And if you do not have access to the system, you can use nmap -sS …

You don't say why you want to know this, but if you really want to know then ask your administrator. Note, blocking ports and blocking webpages are two completely different things.

How to Check If FTP Port 21 Is Not Blocked Jun 16, 2020

How to Check if SMTP Port 587 is Not Blocked: A Step-by

Apr 16, 2018 Troubleshooting Blocked Ports - Concurrency