OpenVPN cookbook discover over 90 practical and exciting recipes that leverage the power of OpenVPN 2.4 to help you obtain a reliable and secure VPN

395 Pages·2017·5.424 MB·English

by  Keijser, Jan Just

OpenVPN Cookbook
Second Edition

Discover over 90 practical and exciting recipes that leverage
the power of OpenVPN 2.4 to help you obtain a reliable and
secure VPN

Jan Just Keijser

BIRMINGHAM - MUMBAI
OpenVPN Cookbook
Second Edition

Copyright © 2017 Packt Publishing

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First published: February 2011
Second edition: February 2017
Production reference: 1100217

Published by Packt Publishing Ltd.
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ISBN 978-1-78646-312-8
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Credits
Author Copy Editor

Jan Just Keijser Pranjali Chury
Reviewer Project Coordinator

Ralf Hildebrandt Izzat Contractor
Commissioning Editor Proofreader

Pratik Shah Safis Editing
Acquisition Editor Indexer

Rahul Nair Tejal Soni
Content Development Editor Production Coordinator

Zeeyan Pinheiro Melwyn D'sa
Technical Editor

Vivek Pala
About the Author
Jan Just Keijser is an open source professional from Utrecht, the Netherlands. He has a
wide range of experience in IT, ranging from providing user support, system
administration, and systems programming to network programming. He has worked for
various IT companies since 1989. He was an active USENET contributor in the early 1990s
and has been working mainly on Unix/Linux platforms since 1995.
Currently, he is employed as a senior scientific programmer in Amsterdam, the
Netherlands, at Nikhef, the institute for subatomic physics from the Dutch Foundation for
Fundamental Research on Matter (FOM). He works on multi-core and many-core
computing systems and grid computing as well as smartcard applications. His open source
interests include all types of virtual private networking, including IPSec, PPTP, and, of
course, OpenVPN. In 2004, he discovered OpenVPN and has been using it ever since.
His first book was OpenVPN 2 Cookbook by Packt Publishing in 2011, followed by Mastering
OpenVPN, also by Packt Publishing, in 2015.
About the Reviewer
Ralf Hildebrandt is an active and well-known figure in the Postfix community. He’s
currently employed at Charite, Europe’s largest university hospital. OpenVPN has
successfully been used at Charite for over 10 years now on a multitude of client operating
systems.
Together with Patrick Koetter, he has written the Book of Postfix.
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Table of Contents
Preface
1
Chapter 1: Point-to-Point Networks
7
Introduction 7
The shortest setup possible 8
Getting ready 8
How to do it… 8
How it works… 10
There's more… 10
Using the TCP protocol 10
Forwarding non-IP traffic over the tunnel 11
OpenVPN secret keys 11
Getting ready 11
How to do it… 11
How it works… 12
There's more… 12
See also 13
Multiple secret keys 13
Getting ready 14
How to do it… 14
How it works… 15
There's more… 16
See also 16
Plaintext tunnel 16
Getting ready 16
How to do it… 16
How it works… 17
There's more… 17
Routing 18
Getting ready 18
How to do it… 19
How it works… 21
There's more… 21
Routing issues 21
Automating the setup 22
See also 22
Configuration files versus the command line 22
Getting ready 22
How to do it… 23
How it works… 23
There's more… 24
Exceptions to the rule 24
Complete site-to-site setup 25
Getting ready 25
How to do it… 25
How it works… 27
There's more… 28
See also 28
Three-way routing 28
Getting ready 28
How to do it… 29
How it works… 32
There's more… 32
Scalability 32
Routing protocols 33
See also 33
Using IPv6 33
Getting ready 33
How to do it… 34
How it works… 36
There's more… 37
Log file errors 37
IPv6-only tunnel 37
See also 38
Chapter 2: Client-server IP-only Networks
39
Introduction 39
Setting up the public and private keys 40
Getting ready 40
How to do it… 41
How it works… 45
There's more… 45
Using the easy-rsa scripts on Windows 45
Some notes on the different variables 45
See also 46
A simple configuration 46
Getting ready 46
[ ii ]