The Debian Administrator's Handbook

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Abstract

A reference book presenting the Debian distribution, from initial installation to configuration of services.

Preface

Many professionals are increasingly embracing Debian GNU/Linux, whose goal to create a rich and flexible distribution that does not require too much maintenance fits their expectations. They generally appreciate its robustness and reliability, its automation of secondary tasks, as well as the coherence brought by the strict application of specifications and therefore the durability of achievements and skills.

At the same time, many influential actors in the computing industry have now come to understand the strategic interest of using an elaborate distribution that is not managed by a commercial entity. Some of their customers also understand — following the same logic — that a software platform that does not depend on agreements between suppliers reduces the constraints they will have after the purchase.

Finally, many beginners discover Debian through the Knoppix and Ubuntu projects, while others “look under the hood” because they want to avoid empiricism.

Debian — which used to be low-profile — was first adopted by passionate users, who were often attracted by the spirit it embodies. They found a project with clear goals and visible achievements, whose developers focus on creating a good design before building — thereby rejecting the deadlines that often compromise the quality of so many other software projects. Debian is led by its very actors. In other words, Debian users join a project that fully benefits from the advantages of free software… so as to produce free software themselves.

The Debian Administrator's Handbook will guide you on your way to autonomy. It could only be written by authors who master both the technical aspects and the inner workings of the Debian project, and who know the needs of seasoned professionals as well as enthusiasts. Raphaël Hertzog and Roland Mas had the required qualities and managed to create and update this book. I thank them very much for their work and have no doubt that reading this book will be both helpful and pleasant.

Nat Makarevitch (PGP/GPG fingerprint: 2010 4A02 9C0E 7D1F 5631 ADF0 453C 4549 0230 D602)

Foreword

Linux has been garnering strength for the last few years, and its growing popularity drives more and more users to make the jump. The first step on that path is to pick a distribution. This is an important decision, because each distribution has its own peculiarities, and future migration costs can be avoided if the right choice is made from the start.

BACK TO BASICS Linux distribution, Linux kernel

Strictly speaking, Linux is only a kernel, the core piece of software sitting between the hardware and the applications.

A “Linux distribution” is a full operating system; it usually includes the Linux kernel, an installer program, and most importantly applications and other software required to turn a computer into an actually useful tool.

Debian GNU/Linux is a “generic” Linux distribution that fits most users. The purpose of this book is to show its many aspects so you can make an informed decision when choosing.

1. Why This Book?

CULTURE Commercial distributions

Most Linux distributions are backed by a for-profit company that develops them and sells them under some kind of commercial scheme. Examples include Ubuntu, mainly developed by Canonical Ltd.; Mandriva Linux, by French company Mandriva SA; and Suse Linux, maintained and made commercially available by Novell.

At the other end of the spectrum lie the likes of Debian and the Apache Software Foundation (which hosts the development for the Apache web server). Debian is above all a project in the Free Software world, implemented by volunteers working together through the Internet.