Xen is an open-source paravirtualization technology that provides a platform for running multiple operating systems on one physical hardware resource, while providing close to native performance. Xen supports several operating systems: Linux, FreeBSD, Windows, and NetBSD. It enables you to easily test, deploy and run your software and services on multiple operating systems with resource isolation and great performance. It is also a terrific way to consolidate your servers, save hardware and maintenance costs, and minimize downtime. Xen is one of the most popular open source projects in the world and vendors like IBM, Sun, HP, RedHat and Novell are working on integrating Xen into their Linux servers. Xen was originally developed in 2003 at the University of Cambridge Computer Laboratory and we now have both commercial and free versions of the Xen hypervisor. The commercial versions are built on top of the open-source version with additional enterprise features. In this book we explore and use the open-source version of Xen. This concise handbook is ideal for professionals who want a user-friendly reference beside them while they get working with Xen and virtualization. Its easy-to-navigate content offers bite-sized walkthroughs for a wide variety of common virtualization tasks using Xen. We use Fedora Core as the host operating system in this book. The book shows you how to add Xen support to it, leads you through the creation of guest domains running different operating systems and follows up by dissecting a range of common virtualization tasks.