And, they didn't have color graphics. They had green monochrome graphics.

Even older ones loaded programs from switches, punch cards, and reel to reel tape. They had overly large typewriters to control them instead of screens.

Please don't talk to me about computers in the 90's, let alone Macs, being fugly.

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Besides, most people would need fifty CDs to back up just a portion of their digital collection of photos, music and movies.

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BTW - I use software RAID (Windows Server and md) exclusively. Mostly for the cost savings, but also because my disk load is pretty low. In fact, for home media sharing, I recommend software RAID -- I've had way more problems migrating and rebuilding arrays with mid-range consumer controller cards than with software.

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Though you could make a mirror of two RAID5 arrays, there wouldn't be a point -- better to go RAID6 with hot spares. (You'd probably have to do it with a software-based mirror on top of 2 hardware-based RAID5s, because no controller card I've seen will mirror RAID5s.. Eh, you could also do it 100% in software).

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The Drobo (and its ilk) are not alternatives to RAID. They are devices that implement RAID, even if they do not make it obvious to the end-user.

LVM is not a replacement for RAID. It can run atop RAID arrays, but its functionality is almost completely different. (In other words, you can implement LVM without RAID, and RAID without LVM, or LVM on RAID array(s)).

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I've never bothered to read up on the subject and now it's all here in a nutshell on my favorite tech blog: Gizmodo!

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FALSE. You can obtain RAID controller add-on cards from anywhere between $13 and $3000 -- You get what you pay for in the low-end range, though. A temperamental RAID controller can cost you all of your data, even if you have a RAID 6 array.

RAID 0 is the bomb...

FALSE. RAID 0 is generally the best performer, but not only does it have no redundancy, it increases the chances that you will lose all of your data. If you lose any 1 of the X disks you have in the array, then all of your data is gone gone gone.

You don't need a new mobo. Just get a raid controller card.

SEMI-TRUE. As I said above, you can indeed do that. You do not need a RAID controller card however, because most OSes nowadays support RAID at the software level. (Windows consumer products generally will only do RAID 0 or 1, whereas Windows server can do RAID 0 through 5, and Linux can do all). Of course, doing RAID at the OS level means more CPU overhead, and a slower array overall (compared to a good RAID controller and depending upon the configuration of the array(s)).

The advantage is that an array created in, for example, Windows, will be transportable into any other Windows system that supports that RAID level. Most cheap controller cards do not exactly follow standards, and so the array may not be transportable. In other words, you are stuck with that brand and model of controller card for the rest of the life of your array -- no upgrading. In fact, trying to change over to a different controller card can wipe all of your data, especially with anything but RAID1 or 0. I've seen it happen (again, mostly with low-end cards).

I've heard most mobo raids use the CPU to do the parity stuff.

TRUE. Most mobo RAIDs are absolute shit, and do use the host CPU for everything. The RAID controller on the mobo is probably going to be the same as the controller chip on a $20 PCIe card, and I wouldn't trust it with a 10ft. data-pole. One major advantage of RAID arrays is their resiliency. Using a crappy controller card completely mitigates that resiliency. (You'd spend, lets say, $400 on disks, but $20 on a RAID card? Sounds like a bad idea).

High-end cards (some too high end for the average consumer) will generally have their own processors and use no more host CPU time than a single-disk controller (this is true of most external RAID enclosures as well), and they will also have a cache. Look for those features in your RAID controllers (but make sure you get a battery-backed write cache if you use the write cache.. that's a story for a different day).

Also, what does RAID imply for BitTorrenters?

RAID is great for torrenting because (if you have a fast enough internet pipe and/or are regularly unpacking RARs) it can increase your disk bandwidth significantly. Torrent up/downloading can stress your disk with a lot of random read/writes (the slowest way to use a disk).

I used a RAID0 array for a while to host my incomplete and completed directories because it could keep up with the many many many random read/writes that torrenting brings. I didn't need redundancy there, because once something was done downloading I'd copy it to my file server (which has RAID1 and RAID5 arrays).

Hope that clears things up.

[/end rant]

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