Set-up an OpenVPN Server on your Mac

[22/05/2015: The content of this post is very very very out of date.]
[17/08/2020: Kext-deprecation note and comment added]

Due to deprecation of kernel extensions in MacOS (10.12 and newer) OpenVPN seems to be defunct on macOS (at least for private servers), please see my comment. I sincerely hope the TunnelBlick development team will take the time and effort to rebuild the client to use the new KPIs in macOS Big Sur, but latest response suggest they have no interest to do so :(

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An OpenVPN Client is easy, just download Tunnelblick. But to connect to your own Mac or maybe a server you own or are the maintainer for at work, you will need an OpenVPN Server set-up. This is how you do it.

IMPORTANT NOTE: Jon Bullard (developer of TunnelBlick) has commented that with recent (beta) versions, much of this article is no longer needed. Please read his comment on the bottom of the article before doing all this :)

1. Install TunTap;

Download and install the package. This will allow your system to create virtual network devices. After install open the Terminal and type

2. Install XCODE if you haven’t already.

3. Install MacPorts if you haven’t already (http://macports.org)

4. Install openvpn

5. Switch to SuperUser mode. Be careful here, you can ruin a lot.

6. Duplicate the installed files to a more common and safe-from-overwrite location.

7. Edit the bottom 8 or so lines (of the vars file) to match your setup

8. Initialize the PKI (Public Key Infrastructure)

9. Now build a server-key

10. And create a key for your first client

Ofcourse, pinocchio is a sample username.

11. Create some other file I don’t know what it does but apparently is needed (Diffie Hellman parameters);

Certificates are created in the subfolder keys (full path /etc/openvpn/easy-rsa/2.0/keys)

12. Copy the files ca.crt, pinnochio.key and pinnochio.crt to a USB stick or very securely to the client machine. We’ll get to those in a different post.

13. Configure the server. Copy the server configuration file to a suitable location.

14 Edit the configuration.

Change the line

if you want to specify a certain IP-address the VPN server must respond to. Useful if you have multiple IP-addresses on your server and only a few are allowed to be used for VPN.

Change the lines

to match your set-up;

And change the line

to 

Change the lines 

to 

And finally, if you want to allow VPN-connected machines to see each other, change the line

to

15. Last step; making the server run on boot;

and copy/past this into the terminal;

Terminate input with CTRL+D

16. Fire up the server

17. Exit Super User mode

next post; setting up the client machine.