As I recall it was an issue with either my router or the actual modem I got from CenturyLink. I would have to go back and actually try again to get specifics. I right I’d eliminated the router as the culprit but I could be wrong about that, I was going back and forth between them. Port forwarding wasn’t doing anything, there was some issue trying to forward between the modem and router, and from what I remember that’s where I ran in to the “yeah you can’t do this try something else” bit in the guide I’d found.
I was basically never able to see the server I had running on any other device. I’d set up firewall permissions as far as I could tell.
It’s been a little bit, I suspect the issue was getting my modem and router to allow that type of traffic. It wasn’t the firewall. I remember spending a lot of time trying to get port forwarding set up so these fucking things would talk to each other the way I wanted and that’s when I hit the “you can’t do this with your set up try something else” message in the last guide I looked at.