[nylug-talk] ATA RAID experience

[vin]

I'm using the adaptec 2400A ata card.  And I'm very happy with it.  I 
previously had it set up in raid 5, and it worked great.  After a hd failure, 
I switched it to raid 1, and after another hd failure, I'm down to one disk, 
and a second that I'm manually backing up to.

I haven't looked at the monitoring under linux.  I was originally dual-booting 
with windows, and was using the monitoring under windows to check status.  I 
check it from time to time from the bootup screen before it boots into linux 
now.  I have very long uptimes under linux, so I really don't even boot my 
desktop anymore.

The adaptec card was detected without a hickup under suse 8.0/2.4.20 during 
initial setup, and the box boots from the raid setup, which is great.  It 
took me a few hours to set everything up under linux, and about 40 hours to 
fix things and re-install all the drivers under the old windows dual boot 
setup to get windows running again.  

Please take the following advice to heart, and follow it.  The original setup 
was raid 5, with three 60 gig hard drives.  I didn't set up a hot spare, 
which the adaptec allows.  When I lost one of the drives in the raid 5, I ran 
out and purchased another maxtor 60 gig drive (two maxtor boxed drives in the 
raid volume).  I couldn't restore the failed drive because apparently the 60 
gig oem drives from maxtor are just slightly smaller (maybe a gig or two, 
possibly less) than the boxed drives when formatted, and the adaptec software 
said that the drive was too small to use in the volume, and refused to 
rebuild.  So I ended up switching to raid 1, and backing up to the newly 
purchased drive manually, which I've been doing ever since.

If you are going to use any of the cards for raid 1, set up the hot spare now, 
not when a drive fails.  Same thing with raid 5.  One unstated benefit of 
raid 5 is if a drive fails, you can return the drive under warranty without 
worrying about handing your (or your employer's) sensitive data over to 
someone else.  If the card on the drive is the cause of the problem, they 
replace the card and reissue the drive as a warranty item.  Or other problems 
that are fixable.

Use the latest drivers.  There's a big difference between the stock driver 
that comes with the adaptec card, and the newer one they put out, in regards 
to performance under raid 5.  And from what I've seen in the 
reviews/benchmarks, don't expect too much benefit from the hardware 
controller.  If the benchmarks are to be believed, in some circumstances its 
hardly noticeable as to how much processing is offloaded to the card. But 
even in this case, it may make all the difference to your situation.

Vin.

On Friday 09 May 2003 10:36, Carlos Alfaro wrote:
> I know its been asked before about compatibility with
> Linux.  I have found 3ware, SIIG, and promise ATA RAID
> controllers.
>
> I like the SIIG for its 5 year warranty but I don't
> know if it was the card that caused me some problems
> in a test linux box and never bothered to check.  The
> 3ware its fully supported under the current Linux
> kernel (but the monitoring utility is not).
>
> I would like to hear from someone who has had used it
> - any of them- and tell me about their experience on
> reliability and the like.  I am using the SIIG at work
> with a windows server and it works well (its not under
> a heave load and I know its just basic software but I
> like the fact that is not an overload on the server
> OS)
>
> I know Adaptec makes an ATA RAID controller but seems
> a bit high in price.  The purpose of the box is to
> hold maybe two 40 Gig HDD on a Pentium III 500 to host
> more.groupware on it.  All I need is the machine to
> stay up in case a HDD goes out.
>
> Thanks in advanced.
>
> Carlos
>