[TriLUG] raid cards

[Tanner Lovelace]

On 2/15/06, Mike Johnson <mike at enoch.org> wrote:
> Brian Weaver wrote:
>
> > My main concern is that if one of my 3ware RAID cards die, how am I
> > suppose to get the data off the drives? I don't know how 3ware chose
> > to write that information or maintain the array information. So I'm
> > stuck with trying to find a new compatable card at what may be an
> > outrageous price.
>
> I totally agree with Weave here.  I've always said, if you are planning
> on buying a hardware RAID card, buy two.  That's the only way you can
> guarantee that you'll be able to get the data off should the controller
> go south.  And yes, RAID cards do die.  Been there, done that, but we
> happened to have an extra.
>
> Software RAID all the way.
>
> Get a SATA controller that is -very- well supported and has low CPU
> utilization and the overhead of the software RAID won't be noticed.

I hear you and for the most part agree with you, too, but I'll just throw
one counter example in here to muddy the waters a bit. :-)

A few months ago, I wanted to try out FreeBSD on my desktop
(which was running an older version of Linux).  However, because
I was using software RAID and because the formats of software
RAID on Linux and FreeBSD are mutually incompatible, I was out
of luck.  I could try FreeBSD, but not access any of the files on
my /home drive.  I even went so far as to consider pulling one drive
out of the array, running it in degraded mode, copying everything
over and then doing the same thing the other way to convert to the
FreeBSD software raid format, but in the end I figured it wasn't worth
it.  (And after reading Kevin's account of his problems trying to do
something similar, I'm glad I didn't!).  So, in this case, hardware
RAID (assuming the hardware was supported in both Linux and
FreeBSD) would have allowed me to do what I want.

But, in general, I'd agree that software RAID is the way to go.
Other than that one item, I've been very happy with my RAID1
setup on a promise TX4 using linux software RAID.

Cheers,
Tanner
--
Tanner Lovelace
clubjuggler at gmail dot com
http://wtl.wayfarer.org/
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