# Preface

This is a book about Linux, a free implementation of Unix for Intel 386 (or higher), Alpha, SPARC, PowerPC, Motorola 680x0 (m68k), and other personal computer and server architectures. In this book, we want to show how you can completely change the way you work with computers by exploring the world of a powerful and free operating system--one that goes against the grain of the traditional PC world. Setting up and running a Linux system can be challenging, rewarding, and a lot of fun; we think that Linux brings a great deal of excitement back into computing. We invite you to dive in, enjoy yourself, and be the first on your block to know what it means to tweak your dot clocks and rdev your kernel image.

We aim this book at readers who are inquisitive and creative enough to delve full-tilt into the world of Linux. Linux represents something of a rebellion against commercial operating systems, and many of its users are the kind of people who like living on the edge of the latest technological trends. Sure, the casual reader can set up and run a Linux system (or hundreds of them!) without much trouble, but the purpose of this book is to dig deeper into the system and bring you completely into the Linux mentality. Rather than gloss over the messier details, we explain the concepts by which the system actually works, so that you can troubleshoot problems on your own. By sharing the accumulated expertise of several Linux experts, we hope to give you enough confidence so that one day you can call yourself a true Linux Guru.

This is the third edition of Running Linux. In this edition, we have completely updated the installation, configuration, and tutorial information to be up-to-date with the latest Linux software distributions (including Red Hat, SuSE, and Debian) and many application packages. The core of the book, however, has not changed much. This was intentional: in the first two editions we made a great effort to make the book as robust as possible, even though Linux itself is under constant development. This philosophy worked remarkably well and has been preserved in this new, updated edition. We think this book will be of use to you for a long time to come.

This book concentrates on the version of Linux for the Intel x86 family of processors (the 386/486, Pentium, Pentium Pro, and Pentium II/III chips). We have also included appendices detailing the installation and basic configuration procedures for several other architectures, including Alpha, SPARC, m68k, and PowerPC ports of Linux. However, apart from the basic installation procedures, the rest of this book, which focuses on using the system, applies to any port of Linux.

Kalle Dalheimer has joined Matt Welsh and Lar Kaufman as co-authors for this third edition. Kalle has been active in the Linux community for some time and was instrumental in the development of KDE (a popular desktop environment for Linux). Kalle has authored most of the new material in this edition, and his particular expertise has brought a fresh perspective to the technical aspects of this book.

In the preface to the first edition, we said that "Linux has the potential to completely change the face of the PC operating system world." Looking back, we think it's obvious that this has already happened. Linux has erupted into the computing mainstream with an amazing force: it has been covered by every major media channel, has helped usher in the so-called "Open Source Revolution," and is widely claimed as the most viable competitor to Microsoft's dominance in the operating systems market. Today, most estimates place the number of Linux users worldwide at over 10 million. Linux has matured to the point where many people don't need to know much about their systems: they can simply install the software and use it. So, perhaps you will find much of the detailed advice in this volume superfluous; at the very least, retain it for historical evidence.

In writing this book, we wanted to make Linux a real choice for the many personal computer users who find themselves trapped within the limitations of commercial operating systems. Because of the cooperative nature of the system, certain aspects of Linux can be confusing or apparently ad hoc. In this book, we've attempted to condense as much wisdom as possible based on correspondence with thousands of users worldwide (and far too much time playing with our own Linux systems). Linux really can change the way you think about computing--this book will show you how.

The world of Linux has changed a lot between the previous edition of Running Linux and this one. But most of these changes have been in its image rather than its substance: Forbes magazine and the Economist are excited about the growth of Linux, major computer companies like IBM, Hewlett Packard, Oracle, and Compaq are supporting Linux in various ways, and the "open source" model (originally known as free software) that Linux exemplifies is all over the news.

Linux itself has improved along the way, and the programs you run on Linux have matured impressively. Linux can now be used for massive, mission-critical servers with multiple processors, clusters, and RAID disk arrays. Since this is a getting-started book, we don't talk about those things. Rather, we concentrate on the more introductory aspects of the system, but we do cover several server-related topics (specifically, setting up Samba and web servers).

A major new development covered in this third edition is KDE. KDE (and GNOME, a similar project) has brought a new, modern look-and-feel to the Linux desktop, making the system poised to conquer the personal productivity computing market once and for all.

In addition to new sections on KDE and Samba, this edition offers introductions to PPP and to building Java programs on Linux. Of course, all the other information has been completely updated as well.

## 0.1. Why People Like Linux

Why on earth would you want to run Linux? Good question. What you have now works, doesn't it? Windows 98 is a good operating system, but it has a lot of limitations. Being tailored for low-end home users, Windows doesn't deliver the performance or flexibility that many people expect out of a PC operating system. Here are a few reasons why people are switching to Linux:

It's free.

  That is, Linux is a freely redistributable clone of the Unix operating system (OS). You can get Linux free from someone who has it, from the World Wide Web, or you can buy it at a reasonable price on CD-ROM from a vendor who has packaged it (probably with added value), possibly with support services.

It's popular.

  It runs on inexpensive Pentium Pro, Pentium II, AMD, and Cyrix chips, and even older 386/486 machines. Linux also runs on personal PCS based on the Intel Pentium architecture, higher-end workstations based on the SPARC or Alpha architecture, PowerPCs, and 68k-based Macs. Linux supports a broad range of video cards, sound cards, CD-ROM and disk drives, printers, scanners, and other devices.

  Linux has an enormous user community presence on the World Wide Web, with many web sites devoted to providing information and discussion about the system. A growing number of commercial software vendors are developing applications for Linux, including Corel WordPerfect, the StarOffice suite from Star Division, and a number of database products from big names such as Oracle, Informix, and IBM.

It's powerful.

  You will be pleased to see how fast the system runs, even with many processes running and with multiple windows open. Linux makes excellent use of the hardware. Many commercial operating systems (including Windows 98) make little use of the advanced multitasking capabilities of the Pentium processor. Linux is native to this architecture and uses them all. A Linux machine with a reasonably fast processor and a sufficient amount of RAM can perform as well, or better, than Unix workstations costing $10,000 or more.

It is of good quality, and runs high-quality software applications.

  Linux is being developed publicly with hundreds of programmers and users refining it, but with the individual vision and focus of its originator, Linus Torvalds. It incorporates the work of universities, companies, and individuals in the form of highly developed compilers, editors, utilities, and scripts that have been developed over the last quarter century. Unlike other new operating systems, Linux already has an enormous base of applications freely available for your use--from major scientific applications, to multimedia tools, to games.

It has full Unix features.

  Linux is a true multiuser, multitasking operating system that supports multiple processors on some systems. It uses the X Window System graphical user interface (GUI) and offers several different integrated desktop environments, including KDE and GNOME. Full networking support (TCP/IP, SLIP, PPP, and UUCP, among others) is available.

It's highly compatible with Windows 95/98, Windows NT, and MS-DOS.

  You can install Linux along with other disk partitions that contain Windows 98 or other operating systems. Linux can directly access files on Windows systems from the floppy or hard drive. Developers are working on emulators for both Windows 98 and MS-DOS, so that eventually you can run commercial applications built for Windows under Linux. Linux does not run under Windows; it is completely independent of it, but features have been added to allow the separate systems to work together.

It is small.

  The basic OS will run on 8 MB of system memory, including a GUI and window manager. A good basic system will fit in 10 to 20 MB of disk storage. (If this seems like a lot of disk space, it's because Linux provides a lot of utilities.) Linux has even been tuned to run on low-memory embedded systems (such as those used in network routers or robots), and in hand-held Personal Digital Assistants such as the PalmPilot!

It is big.

  Some of the larger distributions fill more than 1 GB of uncompressed disk storage in binary files alone. (Full source code is freely available for Linux and is included in many CD-ROM distributions of the software.) The number of powerful utilities and applications ported to Linux grows constantly. You could probably fill several gigabytes of hard disk with them, even without loading up on graphics and audio files. Linux has even been used to build some of the largest supercomputers in the world by networking together dozens of PCs, each running Linux, and using them as one large computer.

  Most Linux users can run a complete system in 300 MB or so of disk space. This includes all the basics, as well as nice extras such as the X Window System GUI, text-processing tools, and development utilities such as compilers and libraries. But if you're a real power user, much more is available.

It's supported.

  The biggest line of support is the many web sites devoted to Linux (along with thousands of newsgroup participants), but you can also contract for support from an independent company or buy a supported version of Linux from one of its distributors.

It's well-documented.

  There is this book (an excellent start!), which is also available in French, German, Japanese, and Chinese. The Linux development community established the Linux Documentation Project (LDP) early on, which maintains a large amount of online documentation about the system. The many books, FAQ lists, and "how-to" documents from the LDP can guide you through almost any task that needs to be done under Linux. Once you get over a few installation humps, Linux is more or less like any other Unix system, so the many general books about Unix use and administration will give you all the help you need. Finally, there is the popular press, which has written hundreds of books on Linux--both introductory and advanced--which have been translated into most major languages around the world.

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