Re: Raid5 Blues

["Stuart Poulton" <stuart.poulton@xxxxxxxxxxxxxx>]

Hi,

You simply can't assume that RAID is fire and forget, it needs a little
looking after, for this reason I'd suggest the following

1 - Don't buy all the drives from one supplier at the same time, the
chances
are they would be from the same manufacturing batch, so a fault in the
batch
is likely to appear on the drives at around the same time.

2 - Turn on any active monitoring and maintainence features of the RAID
system you're using, for example 3ware cards (AMCC) allow the controller to
carry out an active parity check, this will often detec a fault before it
becomes a problem.

3 - RAID Dosn't protect against external physical influences, ensure that
your raid server, is
a - On a UPS
b - Kept in as stable an environment as possible
c - No physically abused, vibrations, and physical knocks on a running
disk spining at 7200rpm isn't going to go down to well with the
drive heads

4 - Ensure that where possible you keep drivers and firware upto date, at
the end of the day theres a human in the system somewhere, and one pint to
many could prove to be downfall for your data.

I've been using RAID successfully using consumer/soho products in a
research
computing environment for the last ~8 years and have yet to suffer any data
loss, yes I've had drives fail, I've had RAID cards die, PSU's blow up, but
no data loss.

Hopefully this helps , I'm happy to answer any questions.

Cheers

Stuart


> There have been several horror stories on this list over the years
that
> have steered me clear of RAID at home.  Better to lose one drive than
the
> lot.