Load balancing improves network performance by distributing traffic efficiently so that individual servers are not overwhelmed by sudden fluctuations in activity. Server Load Balancing is a guide to this critical component of high availability, clustering, and
fault tolerance, all of which provide the infrastructure for reliable Internet sites and large corporate networks.
Much of the information on load balancing comes from vendor-specific manuals that use inconsistent terminology and are often biased toward the products they cover. Server Load Balancing explains to engineers and technicians the concepts and terminology of load balancing and offers practical guidance for planning and implementing it in almost any environment. It includes a configuration guide with diagrams and sample configurations for installing, configuring, and maintaining products from the four major vendors:
Cisco's CSS Series (formerly ArrowPoint)
the Foundry ServerIron series
By comparing several load balancing products, you'll gain a deeper understanding of the technology and how best to use it to improve your network performance. No system administrator responsible for traffic management should be without this practical guide.
Tony Bourke is a private consultant specializing in Unix administration, networking, and load balancing. He has held positions at SiteSmith, GlobalCenter, and Digex. Tony has designed and implemented SLB and Unix architectures for many high-profile and high-traffic web sites. He has published articles in Sys Admin Magazine, Hostingtech Magazine, and Network World. He is one of the leading authorities on the topic of server load balancing and frequently speaks at conferences around the country. He can be reached at email@example.com.
Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of Server Load Balancing is a jacana, a tropical wading bird. There are eight species of jacana, in six genera. The jacana's most remarkable physical characteristic is its long toes. In fact, the jacana has the longest toes (relatively speaking) of any living bird. When in flight, the jacana's toes extend beyond the tip of the its tail. These long, wide-spread toes enable the jacana to walk across the floating leaves of water plants, hence, the names "lotus bird" and "lily trotter," by which some species of jacana are known. As useful as they are when walking on watery surfaces, the jacana's toes make walking on land very difficult, and for this reason you will rarely see a jacana walking on solid ground. For that matter, you will probably never see a jacana at all, as very few of them are found in captivity. They can be found in fresh-water ponds and swamps in tropical regions throughout the world. Jacanas feed mainly on insects, small mollusks, and small fish.
Jacana females are frequently larger than the males and are more aggressive. In most jacana species, the female mates with more than one male and lays more than one clutch of eggs per season. There are typically four glossy, "scribbled" eggs per clutch, laid in nests that float on the water. The male incubates the eggs and raises the young alone. Jacana chicks can swim and dive immediately after hatching. The father doesn't feed the young, as they are able to find and digest their own food, but he does protect and comfort them for the first few months of life. Matt Hutchinson was the production editor and copyeditor for Server Load Balancing. Linley Dolby proofread the book. Nicole Arigo and Linley Dolby provided quality control. Johnna VanHoose Dinse wrote the index.
Emma Colby designed the cover of this book, based on a series design by Edie Freedman. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.
David Futato designed the interior layout based on a series design by Nancy Priest. Neil Walls converted the files from Microsoft Word to FrameMaker 5.5.6 using tools created by Mike Sierra. The text and heading fonts are ITC Garamond Light and Garamond Book; the code font is Constant Willison. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read using Macromedia FreeHand 9 and Adobe Photoshop 6. This colophon was written by Clairemarie Fisher O'Leary.
Years ago, I actually found this book to be a rather handy, conceptual overview of the principles behind load balancing. While it has some vendor-specific details, its greatest asset is helping the IT architect understand the topological options for layout out his redundancy. The diagrams are particularly helpful.
The biggest problem is that it's now rather dated. It has no treatment of SANs or storage virtualization in general. I don't believe it covers CPU virtualization either, such as offered by Parallels. To round things out nicely, a chapter on database clustering would be welcome as well.
I suppose this book would have been a fair read if I knew nothing at all, and was soon going to begin shopping for a load balancing/failover solution...
It explains things in very general concepts... Large pieces of information are left out of the explanations of how these systems really work, and some concepts are simply wrong.
Even forgiving the low-brow content, it is written horribly. What should be a one-paragraph explanation, turns into several pages, because the author chooses to introduce concepts, piece by piece, in the middle of any other concept that even vaguely applies. Imagine reading a novel where each paragraph had 2 trailing pages which defined each word.
Also, even if you just want to know the basics, it still leaves much out. In the Direct Server Return (DSR) section, the author explains each step, and then skips what happens between the time a packet hits the loopback interface, and when it is returned to the client.
The same section is a great example of another problem with the book. The author says that D.S.R. is wonderful because only about 1/8th the processing is done. Not only did the author screw up the ratio that he gave (essentially saying it would cause 8x the load, which contradicting himself in the following text) but he completely left out the fact that the 8x processing load is not gone, but rather shifted to the important servers, rather than the SLB box.
If you have any idea what load balancing is, what a heartbeat is, and what NAT is, you have nothing to learn from this book, except what not to do if you are an author.
If there is some way that I can get a refund for my book, which is in like-new condition, please contact me.
Having been thrusted into a consulting position with a company who uses Alteon-based products, this book has been like a bible to me. I recommend this book to anyone who does not know much about server load balancing but has a need to.
I had high hopes for this title. Tony's O'Reilly article on bridge-path versus
route-path return traffic was interesting and informative. However, the book
is unable to substain any high level of instruction. A few discussions in the book are confusing, and quite a bit of information is repeated too many times (better editing might have helped on these points). However, I'm not sure Tony had a target audience well thought out while writting this book. The small chapter on performance would definitely not be useful for an experienced network admin, and would be little help to someone just starting to work with server load balancers. More in-depth discussion of load balancing setups for particular protocols (POP, SMTP, HTTP, streaming, FTP, etc) would have been helpful. Real world examples, case studies, and "gotchas" about the major vendor's products would have all made this a more useful book. At least a chapter on open source solutions might have been helpful (example, using apache's mod_rewrite and mod_proxy to reverse-proxy CPU intensive parts of a web site to multiple back end machines, leaving the main server to handle basic web file serving).
Unlike the 20 or so O'Reilly titles on my shelf at work, this one will be staying home or returned to the bookstore.
the book is good if you know little about load balancing. But if you look at actual Alteon manual for example, It covers more ideas about load balancing and how it solves problems on different situation but lack a bit of basic theory which it covers well by this book.
It will be good if this book can explain more than those written on the vendors manual.
A waste of good paper. About a half of book is regurgitation of configuration information for four vendors SLB products. In places the exact same paragraphs have been printed twice. For example page 107 discussing VIPs is identical to the page 111 discussion of VIPs.
There is next to no discussion of Open Source solutions or software techniques.
I am disappointed that O'Reilly would publish a book like this. I hope this isn't a negative trend for O'Reilly.