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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."

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Comment: Re:They (well some of them) are mental disorders (Score 1) 412

by Chrisje (#48776113) Attached to: Russia Says Drivers Must Not Have "Sex Disorders" To Get License

You manage to misrepresent transgenderism in one fell and foul swoop there.

Gender, in terms of how the brain is wired, is actually wired into the system before the testes drop or not. To cut a very long and technical story short, you are mentally wired to be male or female regardless of how your body turns out. For a small percentage of society, this means that their brains don't match their physical attributes, and the consequence of this is indeed a life long quest to become "right".

Stigmas and taboos are quite counterproductive for these individuals, and what Russia is doing is a gross violation of human rights. Then again, I don't expect much sympathy from US citizens, because the LGBT community is still under siege in the US as well. Laws are discriminatory, and public discourse is not very accepting of these folks. All you need to do is watch some Fox News and you'll get the gist.

Characterising the transgendered plight as "dress up in women's lingerie" only serves to exacerbate this situation, even if the intentions are quite OK.

Comment: Re: islam (Score 1) 1350

by Chrisje (#48773409) Attached to: Gunmen Kill 12, Wound 7 At French Magazine HQ

"Capitalism" is really quite a useless term. It frames the discussion in terms of a dichotomy that does not exist in reality. The Americans have now even started equating Socialism with Communism and by proxy of that full fledged Marxism, and then turn around to oppose this with "Freedom" or a "Free Market".

Now I have said this in another post, but there is no such thing as a free market. A free market has an unlimited amount of sellers, an unlimited amount of buyers and no regulations whatsoever. As soon as there's a discrepancy between the supply and demand side, like monopolies, cartels, monopsonies the market isn't truly "free".

Then as soon as you regulate the market in any way, shape or form it isn't truly free. Now for those libertarians out there, or those "no-government is good government" folks on this forum: "Capitalism" as translated into free market doctrine really sucks at morality. Do you agree that child labour ought to be illegal? Are you against slavery? Do you think some oversight should exist as to the circumstances under which labour is performed? If you answer yes to any of those questions, you yourself do not believe in a "free" market.

This means we can quit demonizing "Socialists" because of their alleged "anti-freedom" stance, and we can get on with having some constructive discussions on how we want to redistribute assets so as to maximize the welfare of the world population as a whole. Preferably based on fact rather than faintly religious notions.

Now the notions of a "free market", the "trickle-down effect" and most importantly the "rational actor model" that have been put forth by the Chicago school of economics and their ilk have been proven to be wrong and ineffective countless times. It should become clear if you look at the state of the US today, actually. For reference I would point towards the collected works of Joseph Stiglitz and Ha-Joon Chang.

Yet the public at large seems to want to keep paying lip service to these faulty theories and continues politicians, bankers and businessmen to act in accordance to that which is known to fuck up.

If you are saying people act according to "mutual benefit" you are a proponent of the "rational actor model" I talked about earlier, and that notion is bunk. This is not only made clear by Kahneman et al, but if you delve into George Lakoff's work you'll see that even our definition of rational thought is somewhat fictionalized. Dan Gardner will allow you to see how there is nothing rational about our calculation of risk and Barry Schwartz and Dan Azriely have written volumes on how we are impacted by choices.

To cut a long story short: Cognitive science has long proven that we wouldn't know what "mutual benefit" really is if it kicked us in the ass, which is illustrated by the ever narrowing of the definition of "rationality" in the rational actor model. So yes, the invisible hand as you define it is fictitious at best and completely religious at its worst.

We need government and we need to make some moral decisions as to the kind of society we wish to live in, and enforce that notion through the rule of law, also where economic policy and redistribution of wealth are concerned.

Comment: Re:islam (Score 1) 1350

by Chrisje (#48773267) Attached to: Gunmen Kill 12, Wound 7 At French Magazine HQ

But then religion has already lost all meaning. It just doesn't realize it yet.

I understand the need for some notion of spirituality because people can be freaked out by the prospect of a finite and largely meaningless life, so in order not to go insane I guess some of us need imaginary friends and a promise of an afterlife.

However, in daily life neither my religious neighbors nor I do not ask god to charge our mobile phones. We use a charger that was built and engineered by mankind. Similarly, I don't need a god for morality either. Simple empathy will enable us to do the right thing. We can recognize suffering and decide to try and end or minimize it all by ourselves.

I'd even go as far as to say that a morality that hinges on an external factor dictating it is weaker than a fully internalized and autonomous morality.

Given that opening statement, there is no practical and discernible difference between a religion, dogma and ideology.

Comment: Re:islam (Score 1) 1350

by Chrisje (#48773243) Attached to: Gunmen Kill 12, Wound 7 At French Magazine HQ

So much nuance needed here.

It is easy to look at Islam and consider it to be the root of all evil. Quite frankly this strikes me as a clean cut case of confusing correlation with causality.

Let me start by saying I do not condone violence of any kind, whether it's sectarian for any religion we know of or just plain assholery. So I don't condone the invasion of Iraq, the bombing of Gaza or the invasion of Charlie Hebdo's premise in any way, shape or form. Too many innocent and civilian lives are squandered tragically by all of these actions. Whether it's Al Qaeda, Boko Haram, the IRA, ETA, IDF or Rote Armee Fraktion, US Army or Halliburton that's engaging in violence, I don't care. It's all the same barbarism to me when civilians die.

However, I do find myself at odds with the notion of freedom of speech. I'll illustrate by means of a small segway:

Ha-Joon Chang, the Korean economist has once stated that there is no such thing as a free market. A free market has an unlimited amount of sellers, an unlimited amount of buyers and no regulations whatsoever. As soon as there's a discrepancy between the supply and demand side, like monopolies, cartels, monopsonies the market isn't truly "free".

Then as soon as you regulate the market it isn't truly free. Now for those libertarians out there, or those "no-government is good government" folks on this forum: "Capitalism" as translated into free market doctrine really sucks at morality. Do you agree that child labour ought to be illegal? Are you against slavery? Do you think some oversight should exist as to the circumstances under which labour is performed? If you answer yes to any of those questions, you yourself do not believe in a "free" market.

Similarly, my Constitution's Article 7 is colloquially called the Free Speech article, but really what it states is that Censorship is illegal as long as what you are saying, writing or broadcasting DOES NOT BREAK THE LAW. So the law says that hate-speech, slander and lastly "mis-representation of facts for commercial purposes" are all illegal.

As such, you are totally free to think what you like, but you can't say what you like. By that token: Nobody batted an eye when the Dutch courts forbade an organisation that openly advocated pedophilia. In this case, the consensus is that "free speech" should not be so free, think of the children, etc. But as soon as we are looking at insulting religion, speech should be "free".

Now if we look at the colonialist forces that shaped much of the Muslim world, all the way from Afghanistan to Syria, from Baghdad to Algiers, we should also get a notion of the socio-economic circumstances that arose after our collective (French, English, American and to a degree Belgian) intervention in those areas. And we can then safely conclude that those circumstances are highly conducive for violent crime: There is poverty, no rule of law, borders are haphazardly drawn across cultural and religious boundaries, and 19-35 year old males regularly have no prospect of procreating.

Then quite a few people fled these colonial FUBARs, and settled in Europe. This is about 4.5% of Europe's population, and they have been marginalized, discriminated and even treated with violence. If you look at the amount of violent attacks on mosques in the last 12 years, the list is staggeringly large as compared to attacks on synagogues or papers such as Charlie Hebdo.

So we are dealing with an impoverished population that has residual colonial trauma and is constantly being attacked from all angles, and then we wonder why violent excess enters the picture.

This is a very long winded way of saying that as far as taking the piss at Muslims is concerned, White Privilege becomes part of the equation. We can mock the RC Church more freely, because we are the elite and it is an institute of our own making. However, when we mock Islam we need to be mindful of the socio-economic and power structure we created in which these people survive.

It's akin to the difference between a black US citizen dropping the N-word vis a vis a white middle class male dropping the N-word. We need to be more cautious about viewing the whole picture if we are to solve radicalism in our societies.

Comment: Re:Nice (Score 1) 294

by Cyberdyne (#48725745) Attached to: BT, Sky, and Virgin Enforce UK Porn Blocks By Hijacking Browsers

I do have to wonder, though - What will the UK nannies do if essentially the entire country opts out and says "Yeah, thanks, but we want our porn and violence, thankyouverymuch"?

That's almost precisely why this is being done in the first place. A Member of Parliament named Claire Perry saw a bandwagon she could jump on, using a tale she concocted about her daughter Googling for cookie recipes and getting porn instead, and used this as an excuse to hold a "hearing" on the subject. The hearing found that most parents were already aware of parental controls, had the option and chose not to use them; she took this as an excuse to push filters harder, demanding that ISPs make them opt-out rather than opt-in in hopes of boosting uptake. (Funnily enough, several of the people testifying at her "hearing" happened to be from companies involved in the filtering business...)

Since the biggest four ISPs agreed to force all their customers to reiterate specifically that they still don't want filtering, hopefully this will be enough to stop these idiots pushing any harder for a while - albeit having forced them to flush money away buying in a filtering system most customers never wanted. My current (much smaller, tech-savvy) ISP is very much opposed to this nonsense, which is one reason I'm happy to be their customer - though unfortunately this has already drawn government attention (after which, they had to take on an extra member of staff and upgrade transit pipes to handle the increased demand - probably not the result the politician expected!)

Comment: Re:AC current maintained only by tradition? (Score 2) 578

by Cyberdyne (#48724569) Attached to: What Language Will the World Speak In 2115?

I can see applications for DC power distribution in certain circumstances. High-density computing, for one - why have a full mains PSU in every server? It's expensive, more points of failure, and you end up going from mains incoming to DC for the UPSs inverted to AC to send back to the servers converted back to DC for use inside - and those inverters are not that reliable too. It makes more sense to feed all the servers off of DC (Usually 48V - any lower and current gets silly), and have the power supply stuff all centralized. All the servers need is a DC-DC converter for each rail.

Telcos have been doing exactly that for decades now: all their exchanges and much of the optical kit runs on -48V: it's a low enough voltage to be safe to work on when live (negative rather than positive because that protects against corrosion on the wires), easy to combine sources (a diode will do it), no need to "switch" to backup power (just connect your load, battery and source together, job done).

Facebook went the other way for a large server farm, though: running 480V 3-phase AC to the racks (277V per phase). Cleverly, though, they don't need to convert DC from the batteries to AC in power cuts: the mixed DC/AC bus feeds switch-mode power supplies which convert incoming power to DC anyway, so switching between AC utility power and DC battery power doesn't matter. Pretty clever really, IMO.

Comment: Re:One fiber to rule them... (Score 1) 221

by Cyberdyne (#48721387) Attached to: Google Fiber's Latest FCC Filing: Comcast's Nightmare Come To Life

Why not just run one fiber, ditch all the copper, terminate it at the local POP and then allow various vendors access to that fiber and compete for my business?

Home-run fiber per home would get very expensive I think - normally the idea is something like PON (Passive Optical Networking), where a single fiber is split across a few dozen locations, rather like gas, electricity and water/drainage. Telephone service is, I think, unique in using home-run wiring back to the exchange; even there, the faster post-ADSL services such as VDSL share a single fiber link back to the exchange: my current 80/20 service is VDSL2 as far as the cabinet around the corner - all the hundred or so users on that cabinet share a single fiber from there.

Right now in the UK BT have this set up so everyone on FTTC or FTTP is connected to an Ethernet switch in the exchange, with their own VLAN; any ISP can connect their own equipment to that switch and get your VLAN trunked onto their Ethernet port, or they can pay BT to run PPPoE over that and transport it to them. That probably works better in practice than physically patching a few thousand fiber connections directly to different ISPs in each exchange building - my inner geek would love a straight through fiber link, but how much more would that cost?

You know you've landed gear-up when it takes full power to taxi.