Chapter 7: Installing and Configuring Software

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Once you have a Linux system up and running and are acquainted with its operation and administration, you can begin customizing the system. This chapter covers the general problem of software installations. You'll learn about some of the most common, general installation and configuration techniques used by many different software packages. After reading this chapter, you'll have been exposed to a breadth of techniques that cover the majority of installations. The next six chapters provide more detail in the form of specific examples of the concepts discussed in this chapter.

Some of the information in this chapter is rather basic. Users who have installed some software on their own in the past may wish to skip much of the information found here. You can pick up much of the content with a little experience. However, some of the sections and sidebars contain useful information regardless of your level of experience, so you may want to pick and choose from the various topics covered here.

Getting Started

The process of installing software can't really begin until you've done your homework. Once a software package has been identified, a would-be user has to settle some basic logistics involving the software's license and its features and installation procedure.

Just because a software package fills a certain niche doesn't mean it meets a user's needs. The Apache web server, for example, is extremely robust and full-featured. However, Apache is not engineered to be ultra-high-performance; rather, its focus is on correctness and features. If a user's main requirement in a web server is speed, then Apache might not be the right choice. The real first step to installing software is simply to determine whether it meets the needs of the user.

Reading the Documentation

A user should do her homework and research the software through its documentation. The obvious starting points are the software's web site (if it has one), or the nearly ubiquitous "README" file. This documentation also usually includes installation instructions (often in a file called "INSTALL"), so it's a good idea to review those as well. Only after familiarizing herself with the software should a user begin the installation with the steps that follow; it's a real hassle to spend an hour installing and configuring software only to find out that it doesn't quite meet the needs. Unfortunately, sometimes there's no way to know that until after the fact. A few false starts are to be expected.

Accepting the License

Chapter 2 discussed open source software, which is fundamental to Linux and Linux-based systems. Additionally, Chapter 2 listed some example open source licenses, and briefly described some of the differences between them. Most of the software that users encounter for Linux systems is open source and falls under one of those licenses. However, other licenses exist, and of course there is commercial (non–open source) software for Linux. The first step—one that is sometimes overlooked—is for a user to find out if the desired software is legal to use and if the license is acceptable. For open source software, there is typically a file named "LICENSE" that contains everything the user needs to know; commercial software packages frequently have "click-through" license agreements to which a user is explicitly required to agree. In any case, the license must be reviewed prior to installation.

After the user has reviewed the documentation for the software, verified that it meets the needs at hand, and agreed to the license, it's time to actually install the software. The next section lists and describes the basic installation steps, and provides some tips and guidelines.

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