For those setting up dedicated servers with att service.

So little background. I am a former att prem tech, meaning we installed and repaired your internet service and/or tv issues. I posted the begining part of this guide on the r/att side on how to enable ip passthrough. It expanded it to include the valheim server info just as the way I did it to run my server.

Here's quick and hopefully easy way to enable passthrough for your own router for use with an ATT RG.

Once on the att network via wifi or lan. For this example I will use the BG210 model that I have. Other models should be similar

Use your web browser and go to 192.168.1.254

Then go to "Firewall" at the top, You will need the Device access code that is on your RG for this. The menu right below that will be "IP Passthrough" Set the allocation mode to Passthrough. Then hit save.

Hard wire your own router to the first port of the RG and the other to the internet port on your own router.

Another part that I do to help separate ip addresses is within your own router change the IP addresses from the 192.168.1.1 that your RG spits out. My own router starts with the 192.168.2.0 series. So everything that my router spits out starts with the 2.1 series

On your own router. Make sure you port forward the required ports for the game. This also applies to any other games or servers you run. For valheim is ports 2456-2558. You must have those ports open to allow external connections through

For my nighthawk I have to select the internal ip address of your computer you are running the server on. Let's say it's 192.169.2.30. You would select that up and then the ports value of 2456-2458 and type to UDP.

Also if you are using windows, make sure your firewall allows it through as well. Got to your firewall settings and check both public and private for valheim server/game.

This guide will help for any other issues you might have with any other games. You will just need to replace the ports for valheim with the ports numbers and if it's TCP/UDP or both.