How can I install a VPN server on my VPS in order to access the internet through it? If you want to skip the background and methodology behind the script, skip to the section called “Installing OpenVPN on OpenVZ.”
One of the pre-requisites to run common PPTP and IPSEC VPN protocols is PPP. Due to the nature of OpenVZ virtualization, it requires it’s own custom version of the Linux Kernel to run. As a result, ppp is not available for us to use.
So, OpenVPN is the simplest way to get a VPN server running on your VPS since it utilizes the TUN interface /dev/net/tun and creates a tunnel to your client software running on your PC. Then, using simple IPTables rules, you can masquerade or NAT your traffic to your public interface. Sounds complicated? to a degree it can be (depending on your linux knowledge level).
So we have come up with a script that will allow you to install a “simple” version of OpenVPN server and allow you to download the appropriate configuration file (.ovpn & certificate) to import into the OpenVPN client software. This requires no configuration from your side other than running the script and answering some questions in the wizard.
Installing OpenVPN on OpenVZ
The following script will do the following things:
- It will check to ensure tun/tap is enabled. If it isn’t you will need to contact your support department and have it enabled before continuing.
- It will download and install the RPMForge Repository for CentOS (where OpenVPN packages are located)
- It will use YUM and install all the required packages (openvpn openssl openssl-devel)
Once the required packages are installed the script will create a sample easy to use configuration for OpenVPN and put the required files you will need for your Client to connect in /root/openvpn-keys.tgz
It will set OpenVPN to run on boot and create the necessary iptables NAT rules to route your traffic to your primary Public IP address and save it so it will remember when iptables is restarted.
Download the following script (tested and supported on CentOS 5 32bit) and run as root: OpenVPN Install Script
Type the following commands as root:
chmod 700 install-openvpn.sh
- When asked to enter a “Passphrase” do not enter one, leave it blank and just press “enter”
- When asked for Country Code, Province, City… These do not have the be accurate. Any values will do.
- When asked if you want to build/sign the generated certificates enter yes (y).
- It is normal for it to ask you two times for the same information (Since you are generating both client/server keys)
The final step is to download the /root/openvpn-keys.tgz archive, unzip it on your PC and import the .ovpn file in your OpenVPN Client (you can download it here if you haven’t already). This will create a simple button in your client and allow you to quickly establish a VPN connection to your VPS whenever you need it.
Questions? Contact Us or post a comment on this blog so we can clarify anything not mentioned.