Can't reach DDNS webserver from internet when webserver is on VPN connection

Question

I have a mac mini with a webserver on it, it's connected to my local router, and it has a PIA VPN on.

The router is configured with a DDNS (free domain from changeip.com) to the mac mini's local IP. The router port forwards the 8989 port to my webserver so I can access it locally http://192.168.0.7:8989

I can access the webserver from internet when my mac mini have the VPN off, but once I turn the VPN on it's not possible to reach the webserver. Do you guys know why?

Answer 1

It would probably be a VPN policy violation for the VPN client router to allow any traffic to or from the LAN machines to go in or out the WAN port unprotected, instead of through the VPN tunnel.

So you need your router's DDNS client to advertise its in-tunnel VPN client address instead of its WAN public IP address, whenever the VPN tunnel is up.

Or you could reconfigure your VPN policy to no linger be "full tunnel", and to have an exception to omit, from the VPN tunnel, traffic to and from the web server's address and ports. So it can go in/out of the WAN port without being in the VPN tunnel.