Book Image

Mastering OpenVPN

By : Jan Just Keijser, Eric F Crist
Book Image

Mastering OpenVPN

By: Jan Just Keijser, Eric F Crist

Overview of this book

Security on the internet is increasingly vital to both businesses and individuals. Encrypting network traffic using Virtual Private Networks is one method to enhance security. The internet, corporate, and “free internet” networks grow more hostile every day. OpenVPN, the most widely used open source VPN package, allows you to create a secure network across these systems, keeping your private data secure. The main advantage of using OpenVPN is its portability, which allows it to be embedded into several systems. This book is an advanced guide that will help you build secure Virtual Private Networks using OpenVPN. You will begin your journey with an exploration of OpenVPN, while discussing its modes of operation, its clients, its secret keys, and their format types. You will explore PKI: its setting up and working, PAM authentication, and MTU troubleshooting. Next, client-server mode is discussed, the most commonly used deployment model, and you will learn about the two modes of operation using "tun" and "tap" devices. The book then progresses to more advanced concepts, such as deployment scenarios in tun devices which will include integration with back-end authentication, and securing your OpenVPN server using iptables, scripting, plugins, and using OpenVPN on mobile devices and networks. Finally, you will discover the strengths and weaknesses of the current OpenVPN implementation, understand the future directions of OpenVPN, and delve into the troubleshooting techniques for OpenVPN. By the end of the book, you will be able to build secure private networks across the internet and hostile networks with confidence.
Table of Contents (17 chapters)
Mastering OpenVPN
About the Authors
About the Reviewers

Chapter 9. Troubleshooting and Tuning

Usually, it is quite easy to set up a VPN using OpenVPN. This is one of the most attractive features of OpenVPN compared to other VPN solutions. However, sometimes it is necessary to troubleshoot a non-working setup or to tune an existing setup to gain performance.

Troubleshooting and tuning OpenVPN are often overlooked topics. The OpenVPN log files on both client and server side provide a lot of information, but you have to know how to read them. There are also quite a few common mistakes to make when setting up the client and server configuration files. In this chapter, you will learn how to interpret the OpenVPN log files and how to detect and fix some of these common mistakes.

Finally, there is a large difference between a working setup and a setup that works well. Your OpenVPN setup may be functioning correctly, yet users may still complain about poor performance. Getting the maximum performance out of an OpenVPN setup can seem like black magic. In...