Book Image

Troubleshooting OpenVPN

By : Eric F Crist
Book Image

Troubleshooting OpenVPN

By: Eric F Crist

Overview of this book

OpenVPN, 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.
Table of Contents (16 chapters)

File permissions


Best practice often dictates that once operations requiring escalated privileges have been completed, a daemon or process should drop to an unprivileged user. Many of the OpenVPN how-to documents illustrate this by calling the --user and --group configuration parameters. These same instructions, along with other guidance suggest that your configuration, certificates, keys, and other related files have root ownership. This practice prevents an unprivileged user or process from surreptitiously changing keys, routes, and other parameters.

Once OpenVPN reduces its running privileges, it will be unable to re-read the configuration files, certificates, and keys without some additional options. This may be the desired behavior, and it is the more secure configuration though it is not very resilient. When an option such as --ping-restart is used, the OpenVPN process will attempt to restart itself, requiring a re-read of the certificate, keys, and configuration. If privileges have...