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Comment: Re:204 pages or 240? - both are correct (Score 3, Informative) 75 75

The book contains 204 numbered pages. Add in the index, Table of Contents, preface, copyright page, etc, and it hits 240 pages.

I did not do this in an effort to screw with people.

Had it occurred to me beforehand, however... yeah, I would have totally done that to screw with people.

==ml

Comment: UFS vs ZFS (Score 4, Informative) 75 75

PC-BSD is built atop FreeBSD, but it's unquestionably a different thing than FreeBSD.

There are reasons to use ZFS, and other reasons to use UFS. Sometimes you really DO want UFS on raid-10. It depends entirely on the workload.

UFS has been around for decades now. I can't say it's bug free--nothing is--but most of the code paths have been quite well exercised. ZFS is newer and more complex than UFS, and more actively developed.

UFS is likely to remain the default in mainstream FreeBSD, for licensing reasons if nothing else.

+ - Book Review: "FreeBSD Mastery: Storage Essentials", by Michael W. Lucas-> 1 1

Saint Aardvark writes: (Disclaimer: I received a free copy of this book for review. Disclaimer to the disclaimer: I would gladly have paid for it anyway.)

If, like me, you administer FreeBSD systems, you know that (like Linux) there is an embarrassment of riches when it comes to filesystems. GEOM, UFS, soft updates, encryption, disklabels — there is a *lot* going on here. And if, like me, you're coming from the Linux world your experience won't be directly applicable, and you'll be scaling Mount Learning Curve. Even if you *are* familiar with the BSDs, there is a lot to take in. Where do you start?

You start here, with Michael W. Lucas' latest book, "FreeBSD Mastery: Storage Essentials". You've heard his name before; he's written "Sudo Mastery" (which I reviewed previously), along with books on PGP/GnuPGP, Cisco Routers and OpenBSD. This book clocks in at 204 pages of goodness, and it's an excellent introduction to managing storage on FreeBSD. From filesystem choice to partition layout to disk encryption, with sidelong glances at ZFS along the way, he does his usual excellent job of laying out the details you need to know without every veering into dry or boring.

Do you need to know about GEOM? It's in here: Lucas takes your from "What *is* GEOM, anyway?" (answer: FreeBSD's system of layers for filesytem management) through "How do I set up RAID 10?" through "Here's how to configure things to solve that weird edge-case." Still trying to figure out GUID partitions? I sure as hell was...and then I read Chapter Two. Do you remember disklabels fondly, and wonder whatever happened to them? They're still around, but mainly on embedded systems that still use MBR partitions — so grab this book if you need to deal with them.

The discussion of SMART disk monitoring is one of the best introductions to this subject I've ever read, and should serve *any* sysadmin well, no matter what OS they're dealing with; I plan on keeping it around for reference until we no longer use hard drives. RAID is covered, of course, but so are more complex setups — as well as UFS recovery and repair for when you run into trouble.

Disk encryption gets three chapters (!) full of details on the two methods in FreeBSD, GBDE and GELI. But just as important, Lucas outlines why disk encryption might *not* be the right choice: recovering data can be difficult or impossible, it might get you unwanted attention from adversaries, and it will *not* protect you against, say, an adversary who can put a keylogger on your laptop. If it still make sense to encrypt your hard drive, you'll have the knowledge you need to do the job right.

I said that this covers *almost* everything you need to know, and the big omission here is ZFS. It shows up, but only occasionally and mostly in contrast to other filesystem choices. For example, there's an excellent discussion of why you might want to use FreeBSD's plain UFS filesystem instead of all-singing, all-dancing ZFS. (Answer: modest CPU or RAM, or a need to do things in ways that don't fit in with ZFS, make UFS an excellent choice.) I would have loved to see ZFS covered here — but honestly, that would be a book of its own, and I look forward to seeing one from Lucas someday; when that day comes, it will be a great companion to this book, and I'll have Christmas gifts for all my fellow sysadmins.

One big part of the appeal of this book (and Lucas' writing in general) is that he is clear about the tradeoffs that come with picking one solution over another. He shows you where the sharp edges are, and leaves you well-placed to make the final decision yourself. Whether it's GBDE versus GELI for disk encryption, or what might bite you when enabling soft updates journaling, he makes sure you know what you're getting into. He makes recommendations, but always tells you their limits.

There's also Lucas' usual mastery of writing; well-written explanations with liberal dollops of geek humour that don't distract from the knowledge he's dropping. He's clear, he's thorough, and he's interesting — and that's an amazing thing to say about a book on filesystems.

Finally, technical review was done by Poul Henning-Kamp; he's a FreeBSD developer who wrote huge parts of the GEOM and GBDE systems mentioned above. That gives me a lot of warm fuzzies about the accuracy of this book.

If you're a FreeBSD (or Linux, or Unix) sysadmin, then you need this book; it has a *lot* of hard-won knowledge, and will save your butt more than you'll be comfortable admitting. If you've read anything else by Lucas, you also know we need him writing more books. Do the right thing and buy this now.

Link to Original Source
Robotics

Willow Garage Robot Fetches Beer, Engineers Rejoice 114 114

kkleiner writes "Willow Garage has pulled off the ultimate engineering feat: teaching a PR2 robot to fetch you a beer from the fridge. Not only can the PR2 select the correct brew from the fridge, it can deliver, and even open the beer as needed. That's right, all the humans have to do is drink and relax. Prepare yourself for some major robot-envy as you check out the PR2 delivering much-needed refreshment in the video."
Earth

Minnesota Introduces World's First Carbon Tariff 303 303

hollywoodb writes "The first carbon tax to reduce the greenhouse gases from imports comes not between two nations, but between two states. Minnesota has passed a measure to stop carbon at its border with North Dakota. To encourage the switch to clean, renewable energy, Minnesota plans to add a carbon fee of between $4 and $34 per ton of carbon dioxide emissions to the cost of coal-fired electricity, to begin in 2012 ... Minnesota has been generally pushing for cleaner power within its borders, but the utility companies that operate in MN have, over the past decades, sited a lot of coal power plants on the relatively cheap and open land of North Dakota, which is preparing a legal battle against Minnesota over the tariff."
Image

Scientists Say a Dirty Child Is a Healthy Child 331 331

Researchers from the School of Medicine at the University of California have shown that the more germs a child is exposed to, the better their immune system in later life. Their study found that keeping a child's skin too clean impaired the skin's ability to heal itself. From the article: "'These germs are actually good for us,' said Professor Richard Gallo, who led the research. Common bacterial species, known as staphylococci, which can cause inflammation when under the skin, are 'good bacteria' when on the surface, where they can reduce inflammation."

Comment: As the author of several tech books... (Score 1) 325 325

The most important consideration is the format desired by your publisher. If your publisher wants doc files, you get to use Word.

Any publisher's staff is overworked and underpaid, just like the rest of us. If you make your editor work harder because you won't work to the company's requirements, then they won't work as hard on your book. You want them improving your book, believe me. You don't write as well as you think you do. Nobody does.

Will the publisher try to work with you when you present your manuscript in a bastardized mix of LaTeX and POD? Sure. But you won't make friends. And being friends with your publisher's employees is essential if you want your book to actually appear on bookstore shelves.

Operating Systems

+ - FreeBSD Foundation Auction->

agshekeloh writes: "We're auctioning off the very first copy of Absolute FreeBSD off the press as a fundraiser for the FreeBSD Foundation. If you've been waiting for the right opportunity to open up your checkbook and support the Foundation, this is it!

Your generous donation will get you a book before anyone else in the world, signed by the author. The winner will also receive an authentic laser-printed Certificate of Authenticity, suitable for framing or absorbing spilled cola.

The day the book is done the author will drive to the printer and pick up a copy and ship it to the generous winner. This means that you'll get your copy before the other copies arrive at the distributor, let alone in stores.

100% of the auction proceeds go to the FreeBSD Foundation, of course."

Link to Original Source

Algebraic symbols are used when you do not know what you are talking about. -- Philippe Schnoebelen

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