Sounds like you have a firewall blocking incoming IP traffic.

You want Factorio to handle the UDP protocol on port 34197. See the Lightsail firewall guide .

Joining through the browser works because your headless server connected to Factorio's servers first, so it counts as an outgoing ...

I am running a headless Factorio server on a debian system hosted by AWS lightsail. As in, this is not running on my computer or my network, I am hosting it externally.

On the server browser, it shows the name and description that I have listed in my config file.

Other users, and myself, are able ...