Sebastopol, CA--If you work with Cisco routers, it's likely that you use the Internetwork Operating System, or IOS--an extremely powerful and complex operating system with an equally complex configuration language. With a cryptic command-line interface and thousands of commands, IOS doesn't have a reputation for being user-friendly. Yet, as the unifying thread that runs through virtually all Cisco's immense product line, it's difficult to avoid. James Boney, author of Cisco IOS in a Nutshell, Second Edition (O'Reilly $39.95), observes that this is both an advantage and a disadvantage.
"On the one hand," Boney observes, "when you're familiar with one Cisco router, you're reasonably familiar with them all. Someone using a small DSL router in a home office could look at a configuration file for a high-end router at an ISP and not be lost." Boney adds that while that person may not understand how to configure the more esoteric routing protocols or high-speed network interfaces, he'd be looking at a language that was recognizable all the same.
On the other hand, this uniformity means that just about everything has been crammed into IOS at one time or another. "IOS is massive," says Boney. "There's no other way to say it. And it has evolved over many years. The command-line interface isn't graceful and is often non-uniform: many commands don't do what you think they should, and the same command verbs can mean completely different things in different contexts." The volume of documentation available is daunting; with tens of thousands of pages of information, finding what you need to know is a challenge. And of course, getting to Cisco's online documentation may be impossible if your router doesn't work.
"That's why I wrote this book," Boney explains. "It is primarily a quick reference to the commands that are most frequently needed to configure Cisco routers for standard IP routing tasks. This is far from a complete quick ref to all of IOS--such a quick ref would be well over 2000 pages long, and clearly too long to be useful. Therefore, I haven't attempted to cover protocols other than IP (although there is support for everything from AppleTalk to SNA), nor any of the more exotic creatures in the IP space."
Above all, says Boney, "This is a network administrator's book: it represents practical experience with IP routing on Cisco routers and covers the commands that you're likely to need."
Cisco IOS in a Nutshell consolidates the most important commands and features of IOS into a single volume. The new edition has been revised an expanded to cover features that were integrated into Cisco's latest major release, 12.3, along with highlights from minor release 12.4. Some of the new features are AutoSecure, AutoQoS, and the new IOS naming model. Other sections have been expanded to include IS-IS routing, MPLS, new hardware types, while new chapters have been added to cover quality-of-service and multi-casting. Unlike the previous edition, the book also covers non-routing topics, such as VLANs and switching.
The book begins with a brief, example-oriented tutorial that shows how to accomplish common tasks. The bulk of the book is the quick-reference guide to commands. Brief descriptions and lists of options guide the network administrator through figuring out what commands are needed to accomplish any task, from setting up a serial interface to using applications such as packet filtering, address translation, and traffic prioritization. Cisco IOS in a Nutshell may not be the only book a network administrator will ever need on Cisco, but it is one that will be heavily relied on.
- Chapter 14, "Switches and VLANs"
- More information about the book, including table of contents, index, author bio, and samples
- A cover graphic in JPEG format
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