Nilesh R. Mohite
About the Author
Markus Feilner is a Linux professional from Regensburg, Germany and has been working with open source software since the mid 1990s. His first contact with Unix was with a SUN cluster and with SPARC workstations at Regensburg University during his studies of geography, computer science, and GIS. Since the year 2000, he has published several documents used in Linux training all over Germany. In 2001, he founded his own Linux consulting and training company, Feilner IT (http://www.feilner-it.net). Here, and as trainer, consultant, and systems engineer at Millenux, Munich, he focused on groupware, collaboration, and virtualization with Linux-based systems and networks.
He is working as Stellvertretender Chefredakteur at German Linux-Magazine, where he writes about open source software for both printed and online magazines, including the Linux Technical Review and the Linux Magazine International (http://www.linux-magazine.com). He regularly gives speeches and lectures at conferences in Germany. Security and VPN have never left his focus in his publications and articles. Together with Packt, he published OpenVPN: Building and Integrating Virtual Private Networks in 2006 and Scalix: Linux Administrator's Guide in 2008.
He is interested in anything concerning geography, traveling, photography, philosophy (especially that of open source software), global politics, soccer, and literature, but always has too little time for these hobbies.
Markus Feilner supports Linux4afrikaa project bringing Linux computers into African schools.
For more information, please visit http://www.linux4afrika.de.
Acknowledgement
I'd like to thank all the people from the OpenVPN project and mailing lists. Thanks to all the developers and especially to James Yonan for creating such a great software. Thanks to everyone at Packt for working together through the last few years (however tough they were). Thank you for your patience, your cooperative style, and innovative ideas.
And, of course, the most important thank you goes to my co-author Norbert Graf, who always had the right screenshot or configuration at hand.
Thanks to the fantastic staff at the Regensburg University Clinicum, especially at station 21 who helped me get well again and cured me from Leukemia. Thanks to the wonderful city of Regensburg and the great African people all over this continent!
About the Co-author
Norbert Graf is a professional IT specialist from Munich with many years of experience in network security and server virtualization. His special fields of interest are Linux-based firewalls, VMware, and XEN virtualization.
Since 2002, he has been working as a consultant for an IT company near Munich, for customers from the healthcare sector like hospitals or pharmaceutical concerns to small companies.
He made his first experiences with computers with the Commodore C64 learning to program in basic, followed by an x86 processor PC with DOS and Windows. He is still working with Windows and Linux networks every day. His field of work especially includes integrating Linux servers like Proxies or OpenVPN servers in Microsoft Active Directory infrastructures.
Since 2007, he has published several articles (mostly about Windows and Linux cooperation) together with Markus Feilner in the German and International Linux Magazine .
In November 2007, his son Moritz was born and made the whole family very happy.
About the Reviewers
Chris Buechler is the co-founder and Chief Technology Officer of BSD Perimeter LLC, the corporate arm of the pfSense open source firewall distribution. He has more than a decade of IT experience and holds numerous industry certifications including CISSP, SSCP, MCSE, and CCNA among others. He served as the contributing author on security for the book SharePoint 2007: The Definitive Guide from O'Reilly and is the primary author of a book on pfSense to be published by Reed Media in 2009. He has presented on security topics at more than a dozen conferences in the US and Canada. He can be reached at <>
Ralf Hildebrandt holds a degree in computer science and has been working with Unix since 1994. His experience with computers dates back to 1984 and a sturdy old C64. Recently, he changed employer from T-Systems to Charite and became <>
, thus gaining experience in running large listservers.
Ralf is the co-author of The Book of Postfix .
Preface
OpenVPN is an outstanding piece of software that was invented by James Yonan in the year 2001 and has steadily been improved since then. No other VPN solution offers a comparable mixture of enterprise-level security, usability, and feature richness. We have been working with OpenVPN for many years now, and it has always proven to be the best solution. This book is intended to introduce OpenVPN software to network specialists and VPN newbies alike. OpenVPN works where most other solutions fail and exists on almost any platform. Thus, it is an ideal solution for problematic setups and an easy approach for the inexperienced.
On the other hand, the complexity of classic VPN solutions, especially IPsec, gives the impression that VPN technology in general is difficult and a topic only for very experienced (network and security) specialists. OpenVPN proves that this can be different, and this book aims to document that.