Well, UDP seems to be working again on the main instance as well. I am using a new network card, so my IP changed to x.x.x.103 instead of x.x.x.100 which I had permanently bound to my old MAC address. I corrected that, and now it works again on the normal instance. First thought was that UDP was blocked by router since my rules are set for x.x.x.100 only, but why was it working on the /recover instance on my x.x.x.103 IP then?