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Comment You don't need it to read Slashdot (Score 1) 358

I have a degree in theoretical physics, from the UK's top science university, and in my final year I did a course on General Relativity, for which I scored 70% (i.e. a 1st). I then went on to do a PhD in maths (or math for the non-Brits).

Despite the above, I don't fully understand the maths of general relativity. It is really, *really* hard! Likewise for advanced particle physics and quantum mechanics. I get the principles (I think), but unless you're an Einstein type genius, the maths is essentially about learning the rules and applying them. It is not intuitive, and unless you're prepared to write down the equations and work through them for each situation you come across, the maths is going to remain completely opaque.

That said, I still enjoy reading about these subjects on Slashdot and elsewhere. I think it's much more a question of finding good explanations of what the maths means than feeling obliged to work through it yourself.

If you're really keen, I suggest starting with special relativity. The maths is much simpler, but it still requires working through to make sense of the more complex relativistic situations, e.g. questions of simultaneity and so on. If you can manage that and are still keen, come back to general relativity at that point!

Comment It CAN be dodged (Score 2) 173

According to the KISSmetrics site:

For consumers who do not wish to be tracked by KISSmetrics, the freely available AdBlock Plus extension will prevent their information from being tracked by KISSmetrics.

Now, I'm no fan of tracking or advertising, but TFS/A sounds like scaremongering to me, I fail to see how this service is any more "unblockable" than other analytics providers such as Google. Moreover, since many people are signed into Google all the time for things like Gmail, I'd say Google has the capability to tie a lot more personal information to a site visitor in Google Analytics.

That's not to say that Google share said information with GA account holders, but then KISSmetrics claim not to share personally identifiable information either:

KISSmetrics has never, and will never, share personally-identifiable customer information with any third party sites.

Comment Not the only alternative (Score 2) 164

This is an area I have been following with interest, as a number of clients have asked me about ditching their Exchange servers. There are several "open source" alternatives to Exchange, all with their own drawbacks. The main ones I know of are Scalix, Zimbra, Zarafa, OpenXchange, Citadel, and OpenChange/SOGo, although there are others.

OpenChange looks the most promising in the long term, as I believe it's the only one that promises 100% open source compatibility with Outlook. All the others require some kind of plugin, which generally isn't open source. However, as others have noted, OpenChange is nowhere near production ready.

So far I've been recommending Zarafa to clients, because it's the only one that includes an open source ActiveSync plugin for mobile synchronisation (it's called Z-push). Their support is also fairly good. I haven't tested the other alternatives extensively enough to see how they compare in practical terms though, it would be useful to see a simple objective comparison of them (certainly much more useful than fluff pieces like TFA).

Comment Re:I am a nonbeliever (Score 1) 237

Generic strategy for small businesses to migrate to Linux servers? Maybe not. It is definitely possible though, there a variety of Linux Exchange replacements out there at the moment (we've been deploying Zarafa lately, but there are a number of others - I think SOGo is a particularly interesting one at the moment). They're not quite as polished as Exchange but they do everything you mentioned, with the possible exception of Sharepoint (which I've never actually seen anyone use, maybe we're talking about different target audiences).

Most small businesses that I've dealt with (a) don't have the internal expertise to install/manage a Windows server and (b) have glitches and annoyances in their Windows systems. The upshot of (a) is that they're paying someone else to support a server for them and they don't really care whether it's Linux or Windows, they just care that it works. As for (b), they tend to be pragmatic enough to realise that no computer system is going to be perfect, so if they can save money on licensing and support costs by going with a Linux server they're generally prepared to accept that it will not work identically to an Exchange setup. Unless there is some killer feature of SBS that they need they seem to be happy to adapt to some minor changes in functionality* in return for increased stability and lower costs.

* "Changes" does not necessarily mean "reductions", for example Zarafa's web access is significantly better than OWA, and Zarafa also offers (for example) integration with SugarCRM via the Z-merge framework. I'm sure there are similar arguments to made in favour of the other current Linux groupware systems, Zarafa's just the one I'm most familiar with.

Comment Re:Single sign on? (Score 1) 237

Server probably needs Samba4 if you want modern-Windows-clients on a Linux-only server.

Not true, we just migrated one of our clients from a Windows SBS to CentOS, allowing domain logins via OpenLDAP and Samba 3. It works with XP and Win7. The initial setup was a little tricky, the clients certainly wouldn't have been able to do it themselves, but then like virtually all small businesses they don't know enough about Windows Server to set up a domain on that either.

Comment Re:yes... (Score 2, Informative) 387

Three points:

First, paying money to a hosted torrent provider to avoid paying money for media doesn't entirely make sense, unless the poster in on some kind of moral crusade against media companies (which I can understand but don't support).

Second, the ISP won't have been detecting copyright infringement by monitoring the poster's traffic, it will have been picked up by the media company's representatives joining a torrent and logging the participating IP addresses. Moving to a shell account adds an extra link in the chain, but it's still (presumably) traceable to the poster.

Third, as far as the media companies are concerned it's not really about cutting every alleged infringer off, it's just about cutting off/scaring off the majority. I doubt even the RIAA etc are quite so stupid as to believe that *every* illegal download can be prevented. Of course, making downloading more difficult cuts both ways, e.g. can the media companies be bothered to make the extra effort to track down people using torrent hosting accounts?

Comment Re:Bah (Score 4, Informative) 148

Not that the two games are in any way on the same level of polish, but if you're wanting some multiplayer cowboy fps fun on the PC, I suggest checking out Smokin' Guns. It's a free game based on the Quake 3 engine, been around for a few years now, it's showing its age but I've had a fair few entertaining evenings playing it with my gaming buddies.

Comment Why bother? (Score 3, Insightful) 179

Looking at the specs given by the OP, I am wondering why you would go to the trouble of installing Linux on one of these machines (other than geek cred) when you could just get a MIPS based netbook with similar specs that comes with Linux, e.g. the CnMbook. I got one for £90 last year, it's slow as hell but does the job for basic web access etc when I don't want to carry around a full sized laptop.

I might add that putting a full-featured Linux distro (e.g. replacing the basic Linux install it ships with with Debian or the like) on the CnMbook doesn't seem too plausible at the moment, there's just too much tweaking necessary, and this is a machine that ships with a Linux variant installed. Trying to put Linux on one of the ARM machines mentioned by the OP when it isn't even supported by the manufacturer seems like more pain than it's worth to me...

Comment Re:It's not about if it can do the job... (Score 2, Interesting) 307

Most non-geeks don't tend to hoard old computers though. The thing that we technical types tend to forget is that a lot of people don't really think about the speed of their computer, they just use it and accept the fact that it's grindingly slow due to being a few years old, laden down with crapware and viruses as "the way computers are". I know a number of non-technical people who have bought a new computer because they were finding their existing one too slow after they've had it a few years. There's nothing actually wrong with the old computer hardware, once it's been formatted and reinstalled everything's fine again, but most people are going to be more tempted by the idea of buying a cute new netbook for a couple of hundred (fun shopping therapy) than they are by the idea of wiping their boring old current computer system and starting over (confusing techy work).

Comment Wrong approach (Score 1) 466

The way I see it, the OP is approaching this question from the wrong side. I did things the other way round - I have a PhD in maths and ended up in computing. The reason that I studied maths, and the reason I now work in IT, is because that's what interested me at the time. Pick whichever course you find more interesting. You are likely to get better marks and end up being steered towards work that suits you later on. Treating maths like a chore that has to be done so you can get on with programming is the wrong way to go about it - take an interest in the maths itself and the rest will follow.

Incidentally, every job I have had has been programming related and I have used maths from both areas that the OP mentions in my work in the past. The work I currently do involves virtually no maths. This is because I realised I would like to interact with end-users and non-technical people some of the time I'm working, and (in my experience) the hardcore maths side of programming tends away from that sort of interaction. Difficult is not the same as boring, I find understanding people and turning their requests and ideas into useful code much more difficult than bashing out maths code, but ultimately it's proved more rewarding. Follow your interests, even if they may be difficult, and I think you will be happier for it.

Comment Re:Underclocking (Score 5, Insightful) 697

I second this - a few years back I switched my home server to a Mac Mini from an old x86 box, for power draw and space/noise reasons, much like the original poster. At the time I checked out alternatives, but there wasn't much to recommend other machines, all the ones I could find had much more limited storage space. No doubt that has improved recently, but being able to fit any standard 2.5" drive is a big advantage if you want to use it as a file server.

My Mini draws 20W when idling (I tested it with a kill-a-watt). Power use will be higher under heavy load, of course, but your average home server spends most of the time idling. I'm pretty sure the 85W/110W ratings are the maximum the PSU can handle, not the power draw you'd expect in normal use. My box runs a web server, ssh, mail server, file server and various other bits and pieces. X is not installed. It is one of the old PowerPC Minis, which I think draw a bit less than the more recent Intel Minis, but I can't imagine the power draw has increased that much.

My advice to the OP would be to pick up a second hand Mini and use that - there might be machines out there designed specifically as low power home servers, but Minis are fairly easy to come by and easy to install Linux on as people have been doing it for a few years now, even if Apple don't encourage it. If you're thinking about environmental impact as well as your electricity bill, buying a second hand machine is going to be better than buying a new piece of kit. This was another part of my decision to go with a Mini, there are various computers designed to do the sort of thing the OP has asked for, but they're much more niche and consequently hard to find second hand.

By the way, if you choose to use a PowerPC Mini, choose a distro that fully supports PowerPC! When I set up the box Ubuntu still officially supported PowerPC, but it has since been switched to unofficial ports only support, which is pretty flaky. Debian is a much better bet, I am now using that as it is much more reliable (note to anyone who wants to call me on this, I am very happy using Ubuntu on x86 desktop, but my recent experiences of the PowerPC releases have not been favourable).

Some people are suggesting laptops, but I wouldn't recommend one myself. For one thing, they aren't designed or expected to be on all the time, and I suspect you're more likely to run into heating and dust related issues. For another, one of the main advantages of a laptop is that it has a battery and therefore won't require a UPS. However, leaving the machine constantly on and charging is going to kill the battery life fairly quickly, at which point it's not really very useful. On top of that, most laptops use 80W+ when running on mains power. They're usually only designed to save power when running from battery. Obviously you can change the power saving settings, but it's going to be a pain to do so.

Comment Re:I can see plenty of uses for it. (Score 2, Insightful) 557

Never mind development boxes, there are companies that specialise in Mac Mini colocation! I run a couple of these myself (although not colo), they're quiet, don't take up much space, and only draw 20 watts when idling. That said, I use second hand PowerPC Minis with Debian on them, because (as others have also commented) I find the £500 price tag for a new Intel Mini a bit ridiculous.

I'm kind of curious how they managed to fit two drives in, the ones I've opened up didn't have a great deal of space inside and storage capacity has always been a bit of problem because they only take 2.5 inch drives. While this isn't such a problem now, when I first start using a Mac Mini as a file server a few years back it wasn't possible to get a drive to store all the data I wanted.

With two drives I imagine there might be a bit of a cooling problem too, after several months of being on continuously the vents start to get a bit dusty - I know that shouldn't be such a problem in a properly managed server environment, but I can't imagine that's the market they're aiming at with this release.

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