Book Image

OpenVPN Cookbook - Second Edition

By : Jan Just Keijser
Book Image

OpenVPN Cookbook - Second Edition

By: Jan Just Keijser

Overview of this book

OpenVPN provides an extensible VPN framework that has been designed to ease site-specific customization, such as providing the capability to distribute a customized installation package to clients, and supporting alternative authentication methods via OpenVPN’s plugin module interface. This book provides you with many different recipes to help you set up, monitor, and troubleshoot an OpenVPN network. You will learn to configure a scalable, load-balanced VPN server farm that can handle thousands of dynamic connections from incoming VPN clients. You will also get to grips with the encryption, authentication, security, extensibility, and certifications features of OpenSSL. You will also get an understanding of IPv6 support and will get a demonstration of how to establish a connection via IPv64. This book will explore all the advanced features of OpenVPN and even some undocumented options, covering all the common network setups such as point-to-point networks and multi-client TUN-style and TAP-style networks. Finally, you will learn to manage, secure, and troubleshoot your virtual private networks using OpenVPN 2.4.
Table of Contents (17 chapters)
OpenVPN Cookbook - Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Pushing ciphers


Another new feature of OpenVPN 2.4+ is the ability to "push" a cipher or HMAC algorithm from the server to the client. This makes it much easier to switch encryption or HMAC authentication algorithms, provided that all clients are using OpenVPN 2.4. This recipe provides a setup for explicitly pushing a cipher, as well as an explanation of the new cipher negotiation protocol.

Getting ready

This recipe uses the PKI files created in the first recipe from Chapter 2Client-server IP-only Networks. For this recipe, the server computer was running CentOS 6 Linux and OpenVPN 2.4.0. The client was running Fedora 22 Linux and OpenVPN 2.4.0. For the server, keep the server configuration file basic-udp-server.conf from the Server-side routing recipe in Chapter 2Client-server IP-only Networks. For the Windows client, keep the corresponding client configuration file basic-udp-client.ovpn, from the Using an ifconfig-pool block recipe in Chapter 2Client-server IP-only Networks.

How to...