Troubleshooting OpenVPN

Eric F Crist

• Publisher: Packt Publishing
• Year: 2017
• ISBN:
  9781786466938
• Edition: 1
• Topic: Informatique
• Subtopic: Réseaux informatiques

Get the solutions you need to troubleshoot any issue you may face to keep your OpenVPN up and runningAbout This Book• This is the first book on the market that resolves your issues related to troubleshooting OpenVPN• Ensure your organization's private network is protected 24x7 by resolving OpenVPN issues instantly• Save time and costs by troubleshooting to reduce the impact on your businessWho This Book Is ForThe book is for system administrators who are experienced and well versed with OpenVPN. You should possess intermediate to master level proficiency with OpenVPN. All OpenVPN users can leverage this book.What You Will Learn• Diagnose and remediate authentication and authorization problems in OpenVPN• Overcome simple network and startup script errors• Learn OpenVPN log file format and verbosity options• Resolve operating system-specific errors• Discover various troubleshooting techniques to resolve problems in OpenVPN• Improve performance and identify bottlenecks in the network or with hardware• Determine external versus internal network issuesIn DetailOpenVPN, the most widely used open source VPN package, allows you to create a secure network across systems, keeping your private data secure. Connectivity and other issues are a pain to deal with, especially if they are impacting your business. This book will help you resolve the issues faced by OpenVPN users and teach the techniques on how to troubleshoot it like a true expert. This book is a one stop solution for troubleshooting any issue related to OpenVPN. We will start by introducing you to troubleshooting techniques such as Packet Sniffing, Log Parsing, and OpenSSL. You will see how to overcome operating system specific errors. Later on, you will get to know about network and routing errors by exploring the concepts of IPv4 and IPv6 networking issues. You will discover how to overcome these issues to improve the performance of your OpenVPN deployment. By the end of the book, you will know the best practices, tips, and tricks to ensure the smooth running of your OpenVPN.Style and approachThis is a practical and straight-to-the point book that troubleshoots all the issues related to OpenVPN and provides best practices, tips, and tricks.

Troubleshooting OpenVPN

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Troubleshooting OpenVPN

Copyright © 2017 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: March 2017

Production reference: 1150317

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham

B3 2PB, UK.

ISBN 978-1-78646-196-4

www.packtpub.com

Credits

Author Eric F Crist	Copy Editor Dipti Mankame
Reviewer Krzee King	Project Coordinator Judie Jose
Commissioning Editor Pratik Shah	Proofreader Safis Editing
Acquisition Editor Divya Poojari	Indexer Pratik Shirodkar
Content Development Editor Abhishek Jadhav	Graphics Kirk D'Penha
Technical Editor Gaurav Suri	Production Coordinator Shantanu N. Zagade

About the Author

Eric F Crist hails from Cottage Grove, Minnesota, and he works as a product and systems engineer for Abbott. He has a relatively wide range of professional and life experience starting from physical security and access control as a low-voltage technician into software development, system administration, and software development.

Eric has been a core member of the OpenVPN community since 2008 and helps manage the open source online resources. He also wrote ssl-admin, and he is a lead for Easy-RSA, both of which help manage Certificate Authorities and chains.

Eric collaborated with Jan Just Keisjer for the book, Mastering OpenVPN, in 2015, also for Packt.

I would like to sincerely thank my wife, DeeDee, for encouraging me to write this book. Without your prompting, encouragement, and motivation, I would have had a tremendous amount of additional free time and sanity.

About the Reviewer

Krzee King is a self taught BSD/Linux user. He began helping in the OpenVPN community in 2007, when he and the author Eric took control of the IRC channel, and later founded the web forum with Eric and dougy. He believes very strongly in the importance of encryption, and the need for strong encryption to be usable by all. He also had the pleasure of reviewing OpenVPN 2 Cookbook by Jan Just Keijser.

Thanks to my lovely wife and my parents, for their endless support. I love you guys.

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Preface

OpenVPN is arguably the best cross-platform secure networking technology currently available. The development community is large and active every day of the year, with new developers popping up regularly with patches and feature requests. It is not only used by hobbyists, but also by for-pay VPN providers strewn about the Internet.

In Troubleshooting OpenVPN, we identify the most common problems and pitfalls in the deployment of OpenVPN. We demonstrate where and how to use an assortment of diagnostic and investigative tools, both common and lesser known.

By the end of this book, you should be able to understand and identify where a problem resides, both within your VPN infrastructure and also from external causes. The log file is fully detailed and you will be able to leverage the varying logging levels to suit your troubleshooting efforts.

What this book covers

Chapter 1, Troubleshooting Basics, helps the reader break down problems into digestible portions with related components. Some of the concepts discussed include generic techniques useful in more than just OpenVPN problem solving.

Chapter 2, Common Problems, will identify the issues seen most frequently by both novice administrators and experienced administrators alike.

Chapter 3, Installing OpenVPN, covers compilation and installation of OpenVPN on a variety of platforms. Virtual network adapters, alternative client packages, and software dependencies will be identified.

Chapter 4, The Log File, focuses heavily on the Op...

Table of contents

• Troubleshooting OpenVPN