Monthly Archives: February 2010

Mini-review of Beginning OpenVPN 2.0.9 by Markus Feilner and Norbert Graf (Packt Publishing)


This is an edited version of a post that originally appeared on a blog called The Michigan Telephone Blog, which was written by a friend before he decided to stop blogging. It is reposted with his permission. Comments dated before the year 2013 were originally posted to his blog. In order to comply with Federal Trade Commission regulations, I am disclosing that he received a free product sample of the item under review prior to writing the review, and that any links to in this article are affiliate links, and if you make a purchase through one of those links I will receive a small commission on the sale.

Cover of Beginning OpenVPN 2.0.9

I have previously reviewed the title, “Review of OpenVPN: Building and Integrating Virtual Private Networks by Markus Feilner“, and this is the updated and expanded version of that book. The publisher says that all examples in the book work with version 2.0.9 and 2.1 of OpenVPN. Since the original book was released in 2006, it was definitely due for an update!

Here’s what the publisher wants you to know about the book (my comments will follow):

In Detail

OpenVPN is a powerful, open source SSL VPN application. It can secure site-to-site connections, WiFi, and enterprise-scale remote connections. While being a full-featured VPN solution, OpenVPN is easy to use and does not suffer from the complexity that characterizes other IPsec VPN implementations. It uses the secure and stable TLS/SSL mechanisms for authentication and encryption. This book is an easy introduction to this popular VPN application. After introducing the basics of security and VPN, it moves on to cover using OpenVPN, from installing it on various platforms, through configuring basic tunnels, to more advanced features, such as using the application with firewalls, routers, proxy servers, and OpenVPN scripting.

This is a practical guide to using OpenVPN for building both basic and complex Virtual Private Networks. It will save you a lot of time and help you build better VPNs that suit your requirements. While providing only necessary theoretical background, the book takes a practical approach, presenting plenty of examples. It starts with an introduction into the theory of VPNs and OpenVPN, followed by a simple installation example on almost every available platform. After a concise and ordered list of OpenVPN’s parameters, we dive into connecting several machines in a safe way. The last third of the book deals with professional and high-end scenarios, and also mobile integration. After having read the whole book and followed and understood all the examples, you will be an expert in VPN, Security, and especially in OpenVPN Technology. This book was written for version 2.0.9 of OpenVPN, but all examples have been tested and run smoothly on version 2.1 too.
Read the full Table of Contents for Beginning OpenVPN 2.0.9

What you will learn from this book

  • Install OpenVPN on Windows Server, Vista, and Mac OS X and also on different Linux versions and FreeBSD
  • Learn basic security concepts necessary to understand VPNs and OpenVPN in particular
  • Take a look at encryption matters, symmetric and asymmetric keying, and certificates
  • Connect Windows and Linux systems and safely transfer the necessary encryption keys using WinSCP
  • Learn about OpenVPN, its development, features, resources, advantages, and disadvantages compared to other VPN solutions, especially IPsec
  • Discuss non-standard and advanced methods of installing OpenVPN by compiling the source code provided by the OpenVPN project
  • Create an encryption key for OpenVPN and use it to set up an OpenVPN tunnel between two Windows systems in the same network
  • Create X.509 server and client certificates for use with OpenVPN and learn how to use tools to debug and monitor VPN tunnels
  • Create and administer certificates that have to be transferred to the machines that are supposed to take part in the VPN
  • Configure two different firewall networks that connect to each other through the secure OpenVPN tunnel
  • Install and use XCA and TinyCA2 to generate certificate revocation lists that are used to block unwanted connections by formerly authorized clients
  • Install OpenVPN on Windows Mobile and Smartphones running embedded Linux, like Nokia’s Maemo platform
  • Analyze the flow of datagrams between the VPN servers and the connected networks with tools like ifconfig, ping, traceroute, and mtr


This book is an easy introduction to OpenVPN. While providing only necessary theoretical background, it takes a practical approach, presenting plenty of examples. It is written in a friendly style making this complex topic easy and a joy to read. It first covers basic VPN concepts, then moves to introduce basic OpenVPN configurations, before covering advanced uses of OpenVPN.

Who this book is written for

This book is for both experienced and new OpenVPN users. If you are interested in security and privacy in the internet, or want to have your notebook or mobile phone connected safely to the internet, the server in your company, or at home, you will find this book useful. It presumes basic knowledge of Linux, but no knowledge of VPNs is required.

Now back to my mini-review. If you read my original review (which explains why I think a VPN can be an important part of securing private VoIP networks, among other uses), you know that I found Mr. Feilner’s original book quite helpful in giving me a grasp on VPNs, a subject I’d known very little about prior to that point. There were a few things I thought could have been covered better, though, so I was interested to see if those things had been addressed in this updated edition.

As I had more or less noted, the author seemed to slightly prefer SuSE Linux over other versions of Linux, and the Shorewall firewall over other Linux firewall solutions, and (in my opinion) the new book still uses more pages than are really necessary talking about how to set up and configure Shorewall, but at least now the authors do provide some minimal information about the far more popular iptables firewall tool (a little over three pages). It would have been nice to see a more in-depth treatment of this subject, because sometimes setting up iptables correctly is one key to getting your VPN to work as you want it to, particularly if you need or want to do anything more complicated than a simple VPN tunnel. It’s a minor nit, to be sure, because there’s plenty of information on the web about how to set up and configure iptables, but I personally would have given that topic more than three pages.

Then I discovered they’d made one addition that I really wanted to see: A totally new chapter on OpenVPN GUI tools, and in particular, a section on Webmin’s OpenVPN plugin. My disappointment again was that this was not a more exhaustive treatment of the subject. Actually, it’s little more than a mention that the plugin exists, and a few screenshots.  Granted that this was more than appeared in the original volume, and just informing readers of the existence of that plugin is no small thing, but when I did my series on Setting up an OpenVPN tunnel using a CentOS-based system as the server and a router flashed with Tomato firmware as the client, it took me two parts to explain how to configure the Webmin plugin.  That same chapter also talks about some client GUI’s for Linux, but doesn’t spend more than a page or two on any of them.

I’m not really faulting the authors here — it’s very apparent that they write about what they know, and they definitely know their stuff when it comes to OpenVPN, whereas they may not be quite as familiar with Webmin or iptables.  That said, Windows users should find all the information they need to set up an OpenVPN tunnel and then some, and Linux newbies get enough information to at least point them in the right direction. As for Mac users, the coverage there is about the same as in the previous edition, which is to say that there’s about three pages on how to install Tunnelblick.  However, much of the information in the book is not OS specific, and those with some experience with Linux or OS X should have no trouble at all following along.

On a positive note, there are many examples and screenshots in the book, and in this one the screenshots are actually readable (well, I did need my reading glasses for a few of them, but then I’m getting to the point where I need my reading glasses to read the cooking directions on a frozen dinner!). And, the authors’ writing style is clear and easy to understand. Also, there’s a totally new (albeit relatively short) chapter on Mobile Security, which may be of interest to some of the “road warriors” out there.

So, my recommendation is this:  If you read Markus Feilner’s previous book on OpenVPN and liked it, you’re almost certainly going to want to read this one, just to get up to date.  If you didn’t read the previous edition but just want to get up to speed on OpenVPN, this really is one of the better books on the subject, provided that you understand that at times you may have to supplement the book with a bit of additional research on the Web, particularly if you are running OS X or Linux as your operating system (but at least you’ll have a much better handle on topics for additional research).

The reason this is a mini-review and not a full review is because due to personal/family issues I haven’t had time to do much more than skim through the new book, rather than give it a complete read as I normally prefer to do.  But since Packt Publishing kindly sent me the book over a month ago, I feel as though it’s a disservice to both them and to the readers of this blog to delay mentioning it any longer. Despite my comments about the paucity of additional pages on the particular topics I’d hoped to read more about, this is still a great book for those who need to set up and secure an OpenVPN tunnel, particularly if you’re just starting out and know next to nothing about VPNs and/or OpenVPN.

Beginning OpenVPN 2.0.9 by Markus Feilner, Norbert Graf (Amazon affiliate link)