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
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

The OpenVPN management interface


One of the most powerful but less well-known options of OpenVPN is the management interface. The management interface is available on both the server side and the client side. On the server side, it can be used to collect statistics, monitor and control the connected clients, and perform other management related tasks. On the client side, it can be used to query for passwords, enter proxy information for establishing a connection with the VPN server, interact with a PKCS #11 device, and collect client-side statistics.

The OpenVPN plugin for the Linux NetworkManager makes extensive use of the management interface to control the startup and shutdown of the VPN connection.

To use the management interface, add a line management 127.0.0.1 23000 stdin to either the client or the server configuration file. This option instructs OpenVPN to set up the management interface on IP address 127.0.0.1, port 23000, and to use stdin to specify the management password.

If we...