SOLVED Difficulty With Minecraft Server
Our computers are connected by Ethernet cable directly to the ASUS RT–AC86U router. His local IP address in the United States is 192.168.50.166.
The port forwarding settings are:
Service Name Minecraft Source IP: (blank) Port Range Local IP: 192.168.50.166 Local Port: 25565 TCP: BOTH
When he runs Minecraft on his personal computer and directly connects to 192.168.50.166 and connects. However when he enters the external IP (obtained via the "Network Map" page of the router settings) it will give the error:
Failed to connect to the server io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection timed out: no further information
When I try to connect my computer to 192.168.50.166 I get the exact same error from Minecraft.
But here's the kicker ... If I run the server on MY computer (192.168.50.48) and change the Local IP port forward settings according to my preferences, everything works. I can connect to the Minecraft server via either my local IP or an external IP.