I'm running into a major problem playing the Wii U game Splatoon online. It doesn't seem to use specific ports, so you end up doing things like forwarding UDP 30000-65535 to a specific IP, and even then, 99% of the time, the game will not connect. I got into a game *once*, but I didn't change anything. It worked until I left the group, and I haven't been able to connect since.
Most chatter online suggests just putting the Wii U in a DMZ. I'm familiar with DMZ from more basic home routers, where the admin assigns an IP to be "the DMZ". SmallWall's setup is a bit more intimidating. Does it actually require a 3rd interface? Is there a way to declare an IP address to allow all traffic in and out of it on the existing interfaces?
Now that I went and posted that, I think I found a few things I was missing:
Setting the outbound NAT to be (Wii U's Static IP)/32 AND checking the box for "Avoid port mapping" seems necessary. After that's set, REBOOT!!!
I don't think I saw the dialogue box after making that change that said to reboot, but it's just as likely that I didn't read the page close enough. I epically need to go bed now, so I'll do more testing tomorrow. Then I can clean up my spaghetti of NAT rules and see what still works at a minimum.
I've also found 'avoid port mapping' seems to be necessary for consoles to achieve 'open' NAT, and it seems to work for some PC games too, but of course there are still quite a few which are a complete mess with regard to networking and seem to fall apart without uPnP - even if you take the time to forward all of the port ranges they recommend, it still tends to not work properly. Plus it doesn't help matters that the 'tech support' people who make the port-forwarding guides don't understand the difference between firewalls and NAT and seem to include necessary outbound ports like 80 on their list of ports to forward to your PC. :facepalm: