Run something like this on your server: tcpdump -i eth0 port 427 and see if anything shows up. If nothing does, there's some sort of block elsewhere. Check your local firewall with something like iptables -L -n to make sure the INPUT chain permits your traffic.
How to Test If WiFi Ports Are Blocked – Republic Help WiFi ports must be open for WiFi calling to work properly. If a port is blocked, you will get an Error instead of the page telling you it is working. The Port number is the number listed at the end of each website above. Note that PortQuiz is not affiliated with Republic Wireless. Howto find port blocking - Wireshark Q&A Trace on the server and you probably wont see anything unless there is software blocking the port up the stack somewhere. But you can see that with netstat or tcpview. Not entirely 100% sure if you mean the client software is also running on the server or if it is a separate computer. Checking if port is blocked - C# (C sharp): Microsoft Dec 23, 2008
Oct 11, 2017
May 19, 2013 UDP communication is blocked by the Windows Firewall rule Sep 09, 2015
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