Hello,
i have a pretty specific question, how safe/secure is it to use ZeroTier with devices that are behind a VPN Network like MullvadVPN etc…
For example, a Phone that uses ZeroTier access a Server with ZeroTier, but the Server is behind a Router that is connected to a VPN Provider, so the Public IP is shared by numerous people that use the same VPN Profile of the provider.
As i understand it, ZeroTier uses UDP hole punching, but wont it open the UDP port for everyone with that shared IPv4 from the VPN Provider?
I wouldn’t expect this to work. “Privacy” VPNs like Mulvad aren’t going to allow incoming connections to be established. Only incoming packets related to outgoing requests.