Chapter 3. Installing OpenVPN

There is a multitude of clients available to connect to an OpenVPN server. This chapter helps the administrator troubleshoot client installation errors. We will cover both the open source clients as well as a few commercial alternatives. This chapter will cover these topics and help the administrator resolve common problems.

Common installation problems

OpenVPN installation problems can be classified into a few major categories: adapter or driver problems, lack of necessary permissions, and broken installers. It is also possible that the existing packages for your chosen operating system either do not exist or are greatly out of date.

Compiling OpenVPN

On Linux and Unix systems, compiling from source can sometimes be the only way to get OpenVPN installed. There are packages available for the majority of operating system releases, but there are custom systems (Raspberry Pi, BeagleBone, OpenWrt, and so on) that may not have the latest version of OpenVPN available. Given a proper development environment, the OpenVPN installation should be pretty straightforward.

The required development environment basically consists of the following software components:

• autoconf (http://www.gnu.org/software/autoconf/)

• automake (http://www.gnu.org/software/automake/)

• C code compilers, such as gcc, clang, msvc, and cc, should all work...

Alternative clients

From an open source project perspective, the only supported application is a build of the open source project code. In practice, however, there are a multitude of exceedingly useful alternative builds. Some of these builds are for commercial VPN providers, and support not just the OpenVPN protocol, but may include support for PPTP, IPSec, or AnyConnect, or any other protocol. These applications usually provide a single, simple, user interface, and couple with a custom configuration provided by the author or provider.

Because of the added features or controls that may be built into the third-party application, it's likely easiest to troubleshoot a non-working OpenVPN connection by reverting back to the open source client. This helps to rule out the additional features.

There are a few circumstances where an official application does not exactly exist. Mobile platforms, for instance, do not have a native OpenVPN open source build. The Android OpenVPN client, while using the...

Summary

In this chapter, we discussed how OpenVPN is installed and compiled, including some of the benefits of using software packages distributed by your operating system of choice. There are many places where a compilation or installation of OpenVPN can turn sour, and being cognizant of those will help you create a successful and maintainable VPN.

I think the hardest market today is the mobile market, primarily due to the lockdown of some application marketplaces and the restrictions placed on the environment and ecosystem. Being aware of these as well as some of the limitations of a given platform should set up correct and workable expectations.

In the next chapter, we dig into the log file, helping you identify problems and recognize some of the solutions indicated in the log messages. The previous chapters primarily covered the bases of how OpenVPN functions, how it's built, but only works on functional setups.