I use Zerotier at lots of places.
However I have it installed on one Server 2016 instance and it works fine when you start the server up - I can ping it from another client on the same zerotier network.
But the moment someone logs in to it, the zerotier LAN network connection stops. Ping, RDP, everything is dead.
If i reboot and I am pinging the zerotier LAN IP from another node, it starts working once the server is up again. Then when anyone logs in, seconds later zerotier LAN dead again.
However on that machine zerotier-cli listpeers shows all the authorised nodes. And the problem server can also be seen by all the other nodes when they run zerotier-cli listpeers
Firewall totally off for testing
I have an identical server, hosted on identical cloud hosting, with identical setup, identical host firewall rules and it works. I’ve been over it with a fine tooth comb and the only diff i can see is the working one runs 1.4.6 and the non working one runs 1.6.4.
I just rolled it back to 1.4.6 and the problem remains.