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+ - Brain-Inspired "Memcomputer" Built, Could Surpass Quantum Computers->

DorkFest writes:

Inspired by the human brain, UC San Diego scientists have constructed a new kind of computer that stores information and processes it in the same place. This prototype "memcomputer" solves a problem involving a large dataset more quickly than conventional computers, while using far less energy...Such memcomputers could equal or surpass the potential of quantum computers, they say, but because they don't rely on exotic quantum effects are far more easily constructed.

The team, led by UC San Diego physicist Massimiliano Di Ventra published their results in the journal Science Advances.
Link to Original Source

+ - How much did your biggest "tech" mistake cost?

NotQuiteReal writes: What is the most expensive piece of hardware you broke (I fried a $2500 disk drive once, back when 400MB was $2500) or what software bug did you let slip that caused damage? (No comment on the details — but about $20K cost to a client.)

Did you lose your job over it?

If you worked on the Mars probe that crashed, please try not to be the First Post, that would scare off too many people!

+ - Someone Will Die Playing a Game in Virtual Reality

SlappingOysters writes: Grab It has detailed a hands-on session with horror VR title Kitchen — from Resident Evil creator Capcom — and argues how the physical reaction to the experience could lead to death. The site also believes that classifying VR games will be a challenge and many titles could be banned. Virtual Reality has a big year ahead, with the HTC Vive, Oculus Rift and Project Morpheus all set to release, while Microsoft is working on the HoloLens, which the site argues adds a further challenge to traditional gaming.

Comment: "Resistance" (Score 1) 385 385

I don't carry a torch for Rand Paul, but I am grateful for his act of resistance.

You ask what effect is achieved by his resisting. I will reply, unromantically, almost none.

We could argue about public education (did he really reach anyone new who doesn't already know the Patriot Act is evil?) and about self-aggrandizement (was he merely campaigning?).

To my way of thinking, we are living in a time when our votes count for little, our representatives do little for us, and against this condition of a democratic people isolated from control of the state, a sickening reversal of control is instead true: the security state is ascendant and it is our freedom that is waning.

If my apprehension of our position vis-a-vis the state is correct, this means that most protest will be reduced to a minor symbolic key. Its value, then, is in what it symbolizes, and I would say a filibuster on this point of authoritarian government power symbolizes a refusal to surrender casually. A refusal to be cheapened to the point of not caring; a defiance.

Quantifying such things is easy. What is the net benefit? Again, almost zero. But not entirely. A spark is kindled, or if you prefer, a flicker is kept going in a small and dull flame, with the hope that later we may fan it into something bolder and more valuable.

The value of this filibuster is sustaining hope.

+ - Book Review: Networking for System Administrators->

Saint Aardvark writes: (Disclaimer: I received a free copy of this book for writing a review.)

Michael W. Lucas has been writing technical books for a long time, drawing on his experience as both a system and a network administrator. He has mastered the art of making it both easy and enjoyable to inhale large amounts of information; that's my way of saying he writes books well and he's a funny guy. "Networking for System Administrators", available both in DRM-free ebook and dead tree formats, is his latest book, and it's no exception to this trend.

Like the title suggests, this book explains networking to sysadmins — both juniors new to this career, and those who have been around for a while but don't understand how those network folks live or what they need to do their job. If you're one of the latter, you might think "Oh I've read 'TCP/IP Illustrated' — I don't need another networking book." And it's true that there is overlap between these two books. But Lucas also explains about how to work with network folks: dealing with areas of shared responsibility, how to understand where your side ends, and how to talk to a network admin so that everyone understands each other — and more importantly, is both able and happy to help the other. This is something that is out-of-scope for a network textbook, and it's valuable.

So what's in this book? Lucas takes us through all the network layers, explaining how everything fits together. From physical ("If you can trip over it, snag it, break the stupid tab off the plastic connector at its end, or broadcast static over it, it's the physical layer.") to transport and application, he shows practical examples of how the OSI model maps (or doesn't) to the world of TCP/IP. He shows the happy path and the sad path at each layer, explaining how to understand what's going on and troubleshooting failures. This is the part with the strongest overlap with those other network textbooks. If system administration is a side gig (maybe you're a developer who has to maintain your own server), you'll have enough in this book to deal with just about anything you're likely to trip over. But if you're early in your sysadmin career, or you find yourself making the jump to Ops, you will want to follow it up with "TCP/IP Illustrated" for the additional depth.

Since you'll be troubleshooting, you'll need to know the tools that let you dump DNS, peer into packets, and list what's listening (or not) on the network. Lucas covers Linux and Unix, of course, but he also covers Windows — particularly handy if, like me, you've stuck to one side over the course of your career. Tcpdump/Windump, arp, netstat, netcat and ifconfig are all covered here, but more importantly you'll also learn how to understand what they tell you, and how to relay that information to network administrators.

That thought leads to the final chapter of this book: a plea for working as a team, even when you're not on the same team. Bad things come from network and systems folks not understanding each other. Good things — happy workplaces, successful careers, thriving companies and new friends — can come from something as simple as saying "Well, I don't know if it is the network's fault...why don't we test and find out?"

After reading this book, you'll have a strong footing in networking. Lucas explains concepts in practical ways; he makes sure to teach tools in both Unix/Linux and Windows; and he gives you the terms you'll use to explain what you're seeing to the network folks. Along the way there's a lot of hard-won knowledge sprinkled throughout (leave autonegotiation on — it's a lot better than it used to be; replace cables if there's any hint of flakiness in a server's network connection) that, for me at least (and be honest, you too) would have saved a lot of time over the years.

Who would I recommend this book to?
  • If you're a sysadmin at the beginning of your career, this book is an excellent beginning; take it, read it, and build on it — both with practical experience and further reading.
  • If you're coming into system administration the back way (as a developer who has to manage their own server, say, or who shares responsibility for a networked service with other admins), I can't think of a better single source for the practical knowledge you need. You'll gain an understanding of what's going on under the hood, how to diagnose problems you encounter, and how to talk to either system or network administrators about fixing those problems.
  • If you're a manager or senior sysadmin, buy this book and read it through before handing it to the juniors on your team, or that dev who keeps asking questions about routing and the firewall; you may learn a few things, and it's always good to read fine technical writing.

Link to Original Source

Comment: Re: Ummmm.... (Score 1) 319 319

Agreed. What gets forgotten in the debate is that Java is a reference implementation of all true OOP constructs: Interface Abstract Class Class Which when applied judiciously, allow u to do things like inversion of control, dependency injection and test driven development in a strongly-typed environment, and this strongly-typed nature, when properly embraced, makes it easier to write software which you can refactor as often as you desire with orders of magnitude less risk than with "fsck-all-typed" languages like ruby or JavaScript. So, if your application does little more than pushing data into and reading data from some storage engine, then okay, JavaScript is an okay choice. If your application is growing into having significant business logic, then JavaScript will turn into thousands of lines of spaghetti untraceable closure hell , whereby each refactoring attempt will almost certainly have catastrophic consequences in production down some obscure execution path in some anonymous callback function you couldn't be bothered unit testing because how the fsck do you write a unit test against that anonymous function? There's not a concept of a Class in JavaScript. Sure you can mimmick inheritance patterns with prototypes with albeit some unintended consequences (hasOwnProperry) and encapsulated properties by having your closures reference variables from their enclosing context etc, but those techniques are what i call "expressively contrived" Strongly-typed OOP languages have very-well established tried and true patterns for writing test-driven code Ruby while not strongly typed, at least has a concept of Class/methods/inheritance/polymorphism . Problem with Ruby is as i am writing things TDD in it, the first half of my tests are there to ensure that my methods behave correctly when i pass them arguments of the wrong types, and my methods are littered with lines of code ensuring that my arguments have the expected properties. Totally retarded. And Ruby doesn't know anything about an Interface, but that's okay because it's got "fsck-all-typing" so it's not like you would even try to enforce modicums of contracts. Anyway, as applications grow in complexity, building things TDD in strongly-typed OOP languages leads to more fun, and frequent refactoring which makes ur code more stable instead of more brittle. I've written a crap ton of JS code. Java code too. And PHP. And a minimal amount of Ruby: I've appreciated their strengths. And drawbacks. Feel free to learn the same thing I have the hard way: this panacea mentality to stacks is just one big circle jerk. If you think JS, in its current form, is the only true way to build web applications, then by all means, keep that head firmly planted in the sand while the rest of the World out innovates you with a blend of languages and platforms best-suited for their use-cases.

Comment: "Which gets me to thinking..." (Score 1) 690 690

Which gets me to thinking: with free electricity, wouldn't that be a great business opportunity, to build a cloud of servers in poorer Greeks' basements? Maybe that is the real plan behind the free electricity idea.


It's not "thinking," you tone-deaf dolt, to joke about a nation that's suffering a severe depression. Your crack has the moral value of someone saying, "Say, 9-10 would have been a great day to short the airplane industry, har-de-har!"

It's simply you hanging your autism out before the entire board.

Comment: Re:here's an idea (Score 2) 57 57

Here's another idea:

Apple products can be deactivated remotely, even laptops.

Each device has a serial number that can be linked to the gift cards which can be linked to the stolen credit cards.

Do a little bit or leg work, deactivate the illegally obtained devices. Even if you don't nab the thieves, you make this scheme way less profitable.

Comment: Congress'l approval rating near all-time low (Score 1) 667 667

A reminder: sensible men and women have already voted on the merits of Congress.

As Gallup confirmed once more in its December 14 poll, Americans agree on at least one thing in our most divided land. We're led by idiots, chiselers, maniacs and fools:

Americans' job approval rating for Congress averaged 15% in 2014, close to the record-low yearly average of 14% found last year. The highest yearly average was measured in 2001, at 56%. Yearly averages haven't exceeded 20% in the past five years, as well as in six of the past seven years.

+ - 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

Comment: Re:You Kids Get Off My Lawn (Score 4, Interesting) 294 294

"Natural" means "tested by hundreds of thousands of your ancestors who lived to reproduce", provided this is actually true for whatever you're eating.

"Artificial" means "some lab tech trying to feed his/her family on 50k/year synthesized it and then it passed FDA testing without killing anyone or making them sick right away"

Comment: Correct link for buying the book (Score 4, Informative) 83 83

Hi all -- I submitted this review, but it looks like something ate the link for the book. Here's where to buy it:

I believe the Amazon link gives the author a few more shekels, but he makes the most money from the first link; details from his website's page on this book.

+ - Book Review: "Sudo Mastery: User Access Control for Real People"->

Saint Aardvark writes: Disclaimer: I got a free copy of this book because I was a technical reviewer for it. Disclaimer to the disclaimer: I totally would have paid for this book anyway. Final disclaimer: a shorter version of this review appeared on Amazon.com.

If you're a Unix or Linux sysadmin, you know sudo: it's that command that lets you run single commands as root from your own account, rather than logging in as root. And if you're like me, here's what you know about configuring sudo:
  1. Run sudoedit and uncomment the line that says "%wheel ALL=(ALL) ALL".
  2. Make sure you're in the wheel group.
  3. Profit!

Okay, so you can now run any command as root. Awesome! But not everyone is as careful as you are (or at least, as you like to think you are). If you're a sysadmin, you need to stop people from shooting themselves in the foot. (Might also want to stop yourself from self-inflicted gunshot wounds.) There should be some way of restricting use, right? Just gotta check out the man page.... And that's where I stopped, every time. I've yet to truly understand Extended Backus-Naur Form (sue me), and my eyes would glaze over. And so I'd go back to putting some small number of people in the "wheel" group, and letting them run sudo, and cleaning up the occasional mess afterward.

Fortunately, Michael W. Lucas has written "Sudo Mastery: User Access Control for Real People". If his name sounds familiar, there's a reason for that: he's been cranking out excellent technical books for a long time, on everything from FreeBSD to Cisco routers to DNSSEC. He just, like, does this: he takes deep, involved subjects that you don't even know you need to know more about, and he makes them understandable. It's a good trick, and we're lucky he's turned his attention to sudo.

The book clocks in at 144 pages (print version), and it's packed with information from start to finish. Lucas starts with the why and how of sudo, explaining why you need to know it and how sudo protects you. He moves on to the syntax; it's kind of a bear at first, but Chapter 2, "sudo and sudoers", takes care of that nicely. Have you locked yourself out of sudo with a poor edit? I have; I've even managed to do it on many machines, all at once, by distributing that edit with CFEngine. Lucas covers this in Chapter 3, "Editing and Testing Sudoers", a chapter that would have saved my butt. By the time you've added a few entries, you're probably ready for Chapter 4, "Lists and Aliases".

sudo has lots of ways to avoid repeating yourself, and I picked up a few tricks from this chapter I didn't know about — including that sudo can run commands as users other than root. Need to restart Tomcat as the tomcat user? There's a sudoers line for that. I'm ashamed to admit that I didn't know this.

There is a lot more in this book, too. You can override sudo defaults for different commands or users (you can change the lecture text; maybe sometimes there *is* a technical solution for a social problem...). You can stuff sudo directives into LDAP and stop copying files around. You can edit files with sudoedit. You can record people's sudo commands, and play them back using sudoreplay. The list goes on.

Sounds like a lot, doesn't it? It is. But the book flies by, because Lucas is a good writer: he packs a lot of information into the pages while remaining engaging and funny. The anecdotes are informative, the banter is witty, and there's no dry or boring to be found anywhere.

Shortcomings: Maybe you don't like humour in your tech books; if so, you could pass this up, but man, you'd be missing out. There wasn't an index in the EPUB version I got, which I always miss. Other than that: I'm mad Lucas didn't write this book ten years ago.

Score: 10 out of 10. If you're a Linux or Unix sysadmin, you need this book; it's just that simple.

Where to buy:

  • You can buy the ebook version from Lucas himself.
  • You can also buy the ebook or a dead-tree version from Amazon.com.

Link to Original Source

VMS must die!