If you try to install or upgrade several computers at once, you will soon discover that manual installation is a huge time sink. Even if you are working with a checklist, it is often difficult to get everything installed the same way every time. For this reason, most systems administrators understand the importance of an automated install system.

It's no surprise that virtually every operating system has the ability to automate installations. What is curious, given the necessity of such systems, is that configuring automated installation typically requires so much time and effort. In the past, automated installation required a fair amount of knowledge about networking, Pre-eXecutable Environment (PXE), and, of course, the operating system itself. Those prerequisites represented a significant barrier to entry.

Automated provisioning techniques have taken a number of forms over the years. The approach familiar to most people is taking a disk image of a system with the use of dd, PING (Partimage is not Ghost) [1], or another tool, then deploying that disk image anytime you need it. Unfortunately, this solution doesn't scale well because it relies on a uniform environment and does not take into account differences in hardware or function. Also, the image gets out of date over time – with the constant appearance of updates, managing the images can become a full-time job. The more robust way of provisioning is by automatically installing the operating system each time, rather than relying on a predefined disk image. This method is generally considered more challenging.

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