A: Have UPnP enabled on your router. There is often a simple radio button for this on your router configuration page.
-OR-
B: Have a router that does not randomize UDP origin ports.
If you do not have UPnP your server's ping will show up as "---". In this case if your router is non-randomizing your server will still be join-able.
For some reason, I can't host any more. In good ol' v13, I could easily host. Now, even though I have UPnP enabled, no one can join. It just repeats sending four punch packets over and over. In the ded server command prompt, it says "No matches".
My router obviously randomizes UDP ports, as it still isn't join-able with the "---" ping.
blockland works better on a mac than windows IDIOTS
Idiot.