ProtonVPN is a VPN provider that utilizes the OpenVPN protocol.
In order to use this tutorial, one must have a protonvpn account.
Log into ProtonVPN and download one or more OpenVPN configuration files.
Copy the *.ovpn client configuration files into
/etc/openvpn/client/ and make backup of original.
Start your VPN:
# openvpn /etc/openvpn/client/client_config_file.ovpn
Ctrl+C to close the VPN connection.
Saving OpenVPN Authentication
If you get tired of punching in your username and password, you may save your OpenVPN credentials in a separate file and read them automatically.
Enable VPN on Boot
For systemd service configuration, see OpenVPN#systemd service configuration.