Install OpenVPN
Make sure your package repositories and installed programs are up to date by issuing the following commands:

apt-get update
apt-get upgrade --show-upgraded

Begin by installing the OpenVPN software and the udev dependency with the following command:

apt-get install openvpn udev

The OpenVPN package provides a set of encryption-related tools called "easy-rsa". These scripts are located by default in the /usr/share/doc/openvpn/examples/easy-rsa/ directory. However, in order to function properly, these scripts should be located in the /etc/openvpn directory. Copy these files with the following command:

cp -R /usr/share/doc/openvpn/examples/easy-rsa/ /etc/openvpn

Most of the relevant configuration for the OpenVPN public key infrastructure is contained in /etc/openvpn/easy-rsa/2.0/, and much of our configuration will be located in this directory.

Configure Public Key Infrastructure Variables

Before you can generate the public key infrastructure for OpenVPN, you must configure a few variables that the easy-rsa scripts will use to generate the scripts. These variables are set near the end of the /etc/openvpn/easy-rsa/2.0/vars file. Here is an example of the relevant values:

File:/etc/openvpn/easy-rsa/2.0/vars

export KEY_COUNTRY="US"
export KEY_PROVINCE="OH"
export KEY_CITY="Oxford"
export KEY_ORG="My Organization"
export KEY_EMAIL="squire@example.com"