Bernard Golden - Virtualization For Dummies

by Bernard Golden

Virtualization For Dummies

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Copyright 2008 by Wiley Publishing, Inc., Indianapolis, Indiana

Published by Wiley Publishing, Inc., Indianapolis, Indiana

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Library of Congress Control Number: 2007940109

ISBN: 978-0-470-14831-0

Manufactured in the United States of America

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W hen Bernard invited me to write an introduction to this book, I found myself reminded of a frequently repeated conversation with my father, who is a retired engineer. Typically, it goes like this: Simon, what does virtualization do? followed by a lengthy reply from me and then a long pause from my father And why is that useful? Now, I certainly dont think that my father really has much use for server virtualization, but a lot more people do need it and need to understand it than currently use it.

Although virtualization is all the rage in the tech industry press, and savvy market watchers have observed the exciting IPO of VMware, and Citrixs acquisition of my own company, XenSource, the market for virtualization software is largely unaddressed. Depending on whose research you read, only 7 percent or so of x86 servers are virtualized, and only a tiny fraction of desktop or mobile PCs are virtualized. But the virtualization market is white hot, and every day new announcements in storage, server, and network virtualization make the picture more complex and harder to understand.

Virtualization For Dummies is the perfect way to develop a complete understanding of both the technology and the benefits of virtualization. Arguably, virtualization is simply a consequence of Moores Law the guideline developed by Intel founder Gordon Moore that predicts a doubling in the number of transistors per unit area on a CPU every couple of years. With PCs and servers becoming so incredibly powerful, the typical software suites that most users would install on a single physical server a few years ago now consume only a few percent of the resources of a modern machine. Virtualization is simply a consequence of the obvious waste of resources allowing a machine to run multiple virtualized servers or client operating systems simultaneously. But if that were all that were needed, there wouldnt be such a fuss about virtualization. Instead, virtualization is having a profound impact on data center architectures and growth, on software lifecycle management, on security and manageability of software, and the agility of IT departments to meet with new challenges. And it is these opportunities and challenges that urgently need to be articulated to technologists and business leaders alike in an accessible and understandable way.

Having spent many enjoyable hours with Bernard Golden, a recognized open source guru, President and CEO of Navica, and self-taught virtualization expert, I cannot think of a better-qualified author for a book whose objective is to cut through the hype and clearly and succinctly deal with virtualization and its effects on IT and users alike. I always look forward to reading Bernards frequently published commentaries on Xen, VMware, and Linux, which combine his hands-on experience with those products and a rare depth of insight into industry dynamics. I know firsthand that Bernard is a master of the subject of virtualization because he is one of the most persistent and demanding beta testers of XenEnterprise, XenSources server virtualization product, where his feedback has provided us with terrific guidance on how to improve the product overall. This, together with Bernards incisive, clear, and articulate style, makes this book a pleasure to read and a terrific contribution to the virtualization industry a concise categorization of virtualization that will further the understanding of the technology and its benefits, driving uptake of virtualization generally. It is with great pleasure that I strongly recommend that you read this book.

Simon Crosby

CTO, XenSource, Inc.

Bernard Golden has been called a renowned open source expert (IT Business Edge) and an open source guru (SearchCRM.com) and is regularly featured in magazines like Computerworld,InformationWeek, and Inc. His blog The Open Source is one of the most popular features of CIO Magazines Web site. Bernard is a frequent speaker at industry conferences like LinuxWorld, the Open Source Business Conference, and the Red Hat Summit. He is the author of