Programster: CentOS 5.8 - Set up an OpenVPN Server

Introduction

This tutorial will show you how to set up an openvpn server on Centos 5.8 (may work the same way on 6.x). Alternatively, you may want to follow my other tutorial on how to set up on Ubuntu Server 12.04 LTS instead.

Steps

rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm
yum install openvpn

cp -R /usr/share/doc/openvpn/examples/ /home/openvpn

cd /home/openvpn/easy-rsa/2.0/

This is an optional step that may save you time. You can edit the variables in the vars file to set defaults so that you don't have to keep typing in values later. These variables are at the bottom of the file.

vi vars

source vars

Clear out any keys that are already set.

./clean-all

./build-ca

Set up the server variables.

./build-key-server server

Set the client variables.

./build-key client1

If you get an error after running the previous command, it is probably because you entered the exact same details as you did with the server for every field. One of the fields needs to be different.

Generate the keys.

./build-dh

Copy the files you just generated to the directory that actually runs the openvpn service.

cd /home/openvpn/easy-rsa/2.0/keys
cp ca.crt ca.key dh1024.pem server.crt server.key /etc/openvpn

Copy the sample server configuration file to the directory that will run it. We will edit it later.

cd /usr/share/doc/openvpn/examples/sample-config-files

cp server.conf /etc/openvpn/

Copy the sample client configuration as we did with the server. We will edit it later.

cp client.conf /etc/openvpn/

cd /etc/openvpn/

vi client.conf