This is an issue I'm having, I have reserved my computer under the local address 192.168.1.5 instead of static because it proves to be a pain in the long run.
I'm trying to connect using the default port, this case 25565 and I have set the DMZ server to my computer, even made a port rule too to no avail. xhost is off so that's not the issue and the firewall is also off, so I'm pretty confused on why I can't connect using the external IP nor get a port response using a web service, this case http://www.canyouseeme.org/
Regards, White Husky



