@dafyre Well here I am! (Author/founder of ZeroTier)
Reading the above, it seems the issue is active directory DNS. While I know tons about networking, I am not unfortunately an AD expert.
Pertino it seems highjacks DNS. This stuff is in the category of things we want to avoid-- ugly, nasty hacks that fix one thing but likely break everything else. This "enterprise" approach is how Windows networking got in such a bad state to begin with -- in digging into Windows one can see how this or that hack was put in place to make this or that work in an "enterprise" environment, and each hack results in a fractal explosion of edge cases that in turn demand more and more ugly hacks, and so on, until the entire thing becomes the ridiculous ball of garbage that it is today.
But in some cases we have simply been forced to do it. In all such cases we've tried to build such hacks as far from the ZeroTier core as possible. Here's one from WindowsEthernetTap:
https://github.com/zerotier/ZeroTierOne/blob/master/osdep/WindowsEthernetTap.cpp#L902
So let me explain my understanding of this Windows AD DNS issue:
Windows AD DNS likes to automatically register DNS entries for all adapters in the system. When ZT adapters are added, these can collide with, override, or pollute the DNS space with undesired entries. Is this the problem?
If not, can someone explain the issue in a bit more detail? What precisely is going on under the hood? Maybe we can figure out and document a fix that's more elegant.