Question

I’ve spent the last month writing a multiplayer game. I have only been testing it on one machine, using 127.0.01:9051 as the IPEndPoint.

I changed the IP address to my WAN IP, configured port forwarding on my router, configured my software firewall etc… But, it doesn’t connect.

I have checked if the port is open using this site. Result: the port is really open.

Also, when I check the port from that website, my server receives packets just fine; however, when I connect from my own machine… it doesn’t receive anything.

I’ve broken everything down to the basics to make sure it wasn’t a problem with my code.

This basic code does not work:

IPEndPoint iep = new IPEndPoint(IPAddress.Parse("XXX.XXX.XXX.XXX"), 9051);
TcpClient client = new TcpClient();
client.Connect(iep);

Any ideas are much appreciated.

Answer 1

If you are attempting to connect to the IP that is Forwarded (outsideIP) to the same machine (insideIP), it won’t work. There are very few enterprise firewalls and no consumer devices (I know of) that will route a packet from the inside out and translate it back in.

[Internet] — outsideIP[Router/Firewall]insideIP1 — insideIP2[Computer]

In this case, packets from insideIP(X) will not be able to connect to outsideIP.