Preface

A hacker does for love what others would not do for money.

—/usr/games/fortune

The word hack has many connotations. A "good hack" makes the best of the situation of the moment, using whatever resources are at hand. An "ugly hack" approaches the situation in the most obscure and least understandable way, although many "good hacks" may also appear unintelligible to the uninitiated.

The effectiveness of a hack is generally measured by its ability to solve a particular technical problem, inversely proportional to the amount of human effort involved in getting the hack running. Some hacks are scalable and some are even sustainable. The longest running and most generally accepted hacks become standards and cause many more hacks to be invented. A good hack lasts until a better hack comes along.

A hack reveals the interface between the abstract and wonderfully complex mind of the designer, and the indisputable and vulgar experience of human needs. Sometimes, hacks may be ugly and only exist because someone had an itch that needed scratching. To the engineer, a hack is the ultimate expression of the Do-It-Yourself sentiment: no one understands how a hack came to be better than the person who felt compelled to solve the problem in the first place. If a person with a bent for problem solving thinks a given hack is ugly, then they are almost always irresistibly motivated to go one better — and hack the hack, something that we encourage the readers of this book to do.

In the end, even the most capable server, with the most RAM and running the fastest (and most free) operating system on the planet, is still just a fancy back-scratcher fixing the itch of the moment, until a better, faster and cheaper back-scratcher is required.

Where does all of this pseudo-philosophical rambling get you? Hopefully, this background will give you some idea of the mindset that prompted the compiling of this collection of solutions that we call Linux Server Hacks. Some are short and simple, while some are quite complex. All of these hacks are designed to solve a particular technical problem that the designer simply couldn't let go without "scratching." I hope that some of them will be directly applicable to an "itch" or two that you may have felt yourself as a new or experienced administrator of Linux servers.