I'm setting up a VPN so that we can run unencrypted protocols such as Apple File Protocol (AFP) to backup my mother's mac to my Linux server.
I'm using OpenVPN. As a Mac client, you need to install Tunnelblick.
In the Tunneblick configuration folder, you need to put the ca.crt file and client's .crt, .key files.
Then edit the configuration file to point to these files.
The server's IP is 10.31.83.1.