Re: Raid question

Regarding backups, http://jwz.livejournal.com/881573.html is apropos.

As for unraiding the drive, you can do it if you have another drive of
sufficient capacity on hand, usually by something like dd'ing the
filesystem image (ext3 or whatever you have) from the raid to the
other drive. If the original system had an 'optimized' set of kernel
modules, you might have a fun time booting it, but otherwise I've
generally had success with that approach.

On Sun, Jun 29, 2008 at 7:46 PM, Dave Hall <dave-slg@dnh.sk.ca> wrote:
>
> You are correct, you can't "un-RAID" a RAID-0.
>
> Also, I'd like to debunk the suggestion that a RAID-0 is no more risky than a
> single drive.
>
> With a single drive, if the disc fails you lose all your data. With a RAID-0, if
> either drive fails, you lose your data. The probability of data loss doubles.
>
> Think of it like a game of Russian roulette where each drive is a bullet. The
> chance of getting shot doubles when when you put two bullets in the revolver,
> the probability of getting shot doubles.
>
> RAID-0 is purely for improving performance by spreading reads and writes over
> two spindles. RAID-10 or 50 stripes two arrays so it is resistant to a single
> drive failure in either or both RAID-1 or RAID-5 arrays while compensating for
> the slower performance of the RAID-1/5. The RAID is not for disaster prevention
> but minimizing unscheduled downtime. It's not a substitute for backups.
>
> For a home use machine, you're better off with a single disc and some form of
> backup (a removable drive, tape, Internet backup, DVDs, whatever).
>
> As an acid test, if you can't justify spending money on a big UPS and/or a
> generator, then RAID is probably not necessary for your use case.
>
> --
>
> Dave
>
>
> --
> I'm interested in upgrading my 28.8 kilobaud internet connection to a
> 1.5 megabit fiberoptic T1 line. Will you be able to provide an IP
> router that's compatible with my token ring ethernet LAN configuration?
>
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Received on Mon Jun 30 00:28:56 2008