How to hide file server behind VPN?

Question

openvpn

There is one server with NextCloud installed. All connections to it go through Nginx. It acts as a proxy providing HTTPS. You need to raise OpenVPN on the same server and make sure that access to NextCloud is only inside OpenVPN. That is, only OpenVPN clients could reach the files. Can this be done somehow?

Answer 1

Of course you can.
After setting up the VPN, reconfigure NextCloud so that it listens only to the VPN interface.