Hello,

I am having some really strange behavior that may be hard to describe. I'm wondering if anyone else has dealt with this issue in the past.

I am trying to host a minecraft server. I have a connection through AT&T Uverse with the Arris BGW210-700 as my modem/router. I've gone through the steps of forwarding port 25565 to my main desktop computer by going to Firewall > NAT/Gaming > Adding Service with Port 25565 TCP/UDP as both internal/external ports and then adding the custom service on the computer hosting the server. Everything pretty simple up to now.

Then I'll go to canyouseeme.org and it says the port is blocked. Okay. So then I'll restart the router.

Port opens up. I tell my friend to join and they can using my IP address.

I join the server on my minecraft client running on the same machine the server is being hosted on. Again, no issue. But if my friend leaves the server and then tries to join again the port is closed until I restart the server. If I join the server before he has a chance to log in, it closes the port. It's as if my logging in from my LAN closes the port permanently until I restart the Arris modem/router.

I have not tried hosting the server on a different machine yet but I've never had issues with this setup in the past on different ISPs. Anyone know what's going on here or how to fix it?