Hi there

For anybody running Centos 7 as a VM (or even Native - but as this is a Windows Forum I'll assume it's on a VM) this is about the easiest and most foolproof method of getting OPENVPN to work and how to manage those pesky certificates..

How to install OpenVPN Server and Client on CentOS 7

It's easier than you think but not for the faint hearted. Running in a VM is good because if you Hose it up then just start again with a new VM.

Hint - when you first install the Virtual OS save a few copies of the VM!!!

For a small test system you don't need much space. That way if you need to restart or it all goes pearshaped then just delete old VM and power on new one. Ensure though you have at least ONE spare one.

It also helps to have more than one NIC although you can do it with One - in any case on a VM you can presumably add a second virtual NIC and a switch if necessary. You'll have to create a Network Bridge --explained in the documentation.

Have fun !!!

BTW UBUNTU is also another decent distro with documentation for running a VPN too but I'm used to CENTOS.

Test on Local LAN first. Helps if you have another computer such as a Laptop to test connection with - although you CAN do it from the HOST OS. On the HOST OS of course you'll have to install the CLIENT OS if you do it that way. Otherwise install the Client OS on the laptop. OPENVPN Client is available for Windows.

For Windows -- Client :

How to install the Desktop Client on Windows

If you have dynamic IP from ISP you'll need to find out the IP address of your server -- the easiest way is to use CRONTAB to run every so often and pipe the output of ifconfig to a small file and email it to yourself so if the dynamic IP changes you can logon with the new IP address. - Cheaper than paying for a Domain or using something HIDEOUS like Teamviewer.

You can FIX the local LAN address of your server so that any port routings from the outside are directed to the correct machine. A VM behaves exactly as a physical machine in this regard.