VPNLinux
From Amahi Wiki
VPN Client - Linux
The VPN client for Linux comes with the OpenVPN. It's invoked with a script.
Save this script to a file called myvpn.conf. Replacing XYZ for the nickname of the HDA you are trying to connect to:
remote XYZ.yourhda.com 1194 client dev tun proto udp resolv-retry infinite nobind persist-key persist-tun ca ca-cert.crt cert AmahiHDAClient.crt key AmahiHDAClient.key comp-lzo verb 3 auth-user-pass
Be sure to also have a copy of the certificate files using the same names as the ca, cert, and key lines above.
Then, as root, run the openvpn client software:
openvpn --config myvpn.conf
Many messages should scroll by on your terminal screen and you should be requested for your username and password. Enter your HDA username here.