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

Submitted by Saint Aardvark
Saint Aardvark (159009) 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

+ - Winston Churchill's Scientists

Submitted by HughPickens.com
HughPickens.com (3830033) writes "Nicola Davis writes at The Guardian that a new exhibition at London’s Science Museum tiitled Churchill’s Scientists aims to explore how a climate that mingled necessity with ambition spurred British scientists to forge ahead in fields as diverse as drug-discovery and operational research, paving the way for a further flurry of postwar progress in disciplines from neurology to radio astronomy. Churchill "was very unusual in that he was a politician from a grand Victorian family who was also interested in new technology and science,” says Andrew Nahum. “That was quite remarkable at the time.” An avid reader of Charles Darwin and HG Wells, Churchill also wrote science-inspired articles himself and fostered an environment where the brightest scientists could build ground-breaking machines, such as the Bernard Lovell telescope, and make world-changing discoveries, in molecular genetics, radio astronomy, nuclear power, nerve and brain function and robotics. “During the war the question was never, 'How much will it cost?’ It was, 'Can we do it and how soon can we have it?’ This left a heritage of extreme ambition and a lot of talented people who were keen to see what it could provide."

According to Cambridge Historian Richard Toye, Churchill was a “closet science-fiction fan” who borrowed the lines for one of his most famous speeches from H. G. Wells — to depict the rise of Hitler's Germany. "It's a bit like Tony Blair borrowing phrases from Star Trek or Doctor Who," says Toye. A close friend of Wells, Churchill said that The Time Machine was “one of the books I would like to take with me to Purgatory”. Wells and Churchill met in 1902 and several times thereafter, and kept in touch in person and by letter until Wells' death in 1946. "We need to remember that there was a time when Churchill was a radical liberal who believed these things," Toye adds. "Wells is often seen as a socialist, but he also saw himself as a liberal, and he saw Churchill as someone whose views were moving in the right direction.""

+ - Laser that is powered by one electron at a time-> 1

Submitted by Taco Cowboy
Taco Cowboy (5327) writes "Princeton University researchers have built a rice grain-sized laser powered by single electrons tunneling through artificial atoms known as quantum dots. The tiny microwave laser, or "maser," is a demonstration of the fundamental interactions between light and moving electrons

The researchers built the device — which uses about one-billionth the electric current needed to power a hair dryer — while exploring how to use quantum dots, which are bits of semiconductor material that act like single atoms, as components for quantum computers

The device demonstrates a major step forward for efforts to build quantum-computing systems out of semiconductor materials, according to co-author and collaborator Jacob Taylor, an adjunct assistant professor at the Joint Quantum Institute, University of Maryland-National Institute of Standards and Technology. "I consider this to be a really important result for our long-term goal, which is entanglement between quantum bits in semiconductor-based devices" Taylor said

The researchers fabricated the double quantum dots from extremely thin nanowires (about 50 nanometers, or a billionth of a meter, in diameter) made of a semiconductor material called indium arsenide. They patterned the indium arsenide wires over other even smaller metal wires that act as gate electrodes, which control the energy levels in the dots

To construct the maser, they placed the two double dots about 6 millimeters apart in a cavity made of a superconducting material, niobium "This is the first time that the team at Princeton has demonstrated that there is a connection between two double quantum dots separated by nearly a centimeter, a substantial distance" Taylor said

When the device was switched on, electrons flowed single-file through each double quantum dot, causing them to emit photons in the microwave region of the spectrum. These photons then bounced off mirrors at each end of the cavity to build into a coherent beam of microwave light

One advantage of the new maser is that the energy levels inside the dots can be fine-tuned to produce light at other frequencies, which cannot be done with other semiconductor lasers in which the frequency is fixed during manufacturing, Petta said. The larger the energy difference between the two levels, the higher the frequency of light emitted

"In this paper the researchers dig down deep into the fundamental interaction between light and the moving electron" Gmachl said. "The double quantum dot allows them full control over the motion of even a single electron, and in return they show how the coherent microwave field is created and amplified. Learning to control these fundamental light-matter interaction processes will help in the future development of light sources""

Link to Original Source

+ - Patriot Act Idea Rises in France, and Is Ridiculed->

Submitted by PolygamousRanchKid
PolygamousRanchKid (1290638) writes "After shootings last week at a satirical newspaper and a kosher market in Paris, France finds itself grappling anew with a question the United States is still confronting: how to fight terrorism while protecting civil liberties. The answer is acute in a country that is sharply critical of American counterterrorism policies, which many see as a fearful overreaction to 9/11.

Valérie Pécresse, a minister under former President Nicolas Sarkozy, said France needed its own version of the USA Patriot Act, which gave the United States more authority to collect intelligence and pointed America’s surveillance apparatus at its citizens. Politicians and civil rights advocates on both sides of the Atlantic bristled at that suggestion, and at a string of arrests in which French officials used a new antiterrorism law to crack down on what previously would have been considered free speech.

Dominique de Villepin, the former French prime minister, warned against the urge for “exceptional” measures. “The spiral of suspicion created in the United States by the Patriot Act and the enduring legitimization of torture or illegal detention has today caused that country to lose its moral compass,” he wrote in Le Monde, the French newspaper."

Link to Original Source

Comment: Re:It's The American Drean (Score 1) 1313

by TexNex (#42975325) Attached to: US CEO Says French Workers Have Three-Hour Work Day

And those '47%-ers'? The vast majority of them are in one of two categories: a) enlisted in the military, or b) retired

Sorry to burst your bubble but, the enlisted ranks must pay federal tax on their earnings. At their (below E-4) pay rate they most certainly fall into poverty level and most get everything back after filing their return. You should see what a Private makes, minimum wage would be nice.

Comment: Re:Do they realise... (Score 1) 426

by TexNex (#40140605) Attached to: 'Eco-Anarchists' Targeting Nuclear and Nanotech Workers

It's deja vu all over again. In the other period of American history where corporate money had much undue influence, labor unions arose. The businesses hired thugs to terrorize and even execute labor union leaders.

And now its the labor union thugs doing terrorizing...for the people of course.

Comment: Re:Promised bandwidth? (Score 1) 160

by TexNex (#36983512) Attached to: Measuring Broadband America Report Released
Sorry to whomever he was replying to but, I'm going to dig the hole a tad deeper...currently (going on about 10 years now) the US govenment has issued multiple grants for a Bandwidth study with "purpose" of extending reach into rural areas and improving overall speed (links to the posted FCC stuff). One of the largest "non-profit" organizations taking advantage of this grant provides data for around 20 states and is so closely tied to the telecom industry a circle jerk isn't possible.
My town paper http://www.statesman.com/business/survey-texas-companies-with-broadband-internet-outperform-those-1686241.html was nice enough to give them some coverage. See if you can spot the errors.

Comment: Re:Really bad idea. (Score 1) 1173

by TexNex (#36679390) Attached to: Roundabout Revolution Sweeping US

Dude, thats Riverside...mostly college kids who haven't the common sense gave a summer squash. Add to that the congestion at the IH-35 intersection as well as the Montopolis BS (ACC Riverside campus close to the AMD fab) and you have a major traffic problem. The city of Austin would be better served if they restricted downtown traffic to only bike, mass transit, & delivery so all the college kids could leave their cars at home. City council might actually do that if they get the light rail stuff approved. Austin street planning was never plotted for the growth its experiencing, ask some of the old residents they can tell you the city council was activly resisting growth for a long while.

Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (7) Well, it's an excellent idea, but it would make the compilers too hard to write.

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