Need help with RAID question. I think something is really screwed up!!!

[conf22]

I'll try to keep this brief.
I set up a new system (described below).
The I set up a RAID 5 array using an external enclosure and four
Western Digital WD5000YS (enterprise) drives.
I set up the array and it worked.
I loaded all my data to it. It worked.
I loaded software to the system (to a non-raid drive on the built in
controller, not the RAID controller).
Everything worked fine.
Yesterday the controller advised me that a drive in the array failed
and that the "logical device degredated". I rebuilt the array. That
took about 11 hours!

Today, the same thing happened. All of a sudden, everything locked up
for a minute and then the alarm went off. When I looked, a different
drive caused an error.

I had the drive rebuilt. When it was about 12% finished, the alarm
went off again indicating another drive failure in a different drive.
This time it couldn't rebuild since there were only two out of four
drives remaining.

My questions are:

1. Am I doing something wrong?
2. Is there any way to force the controller to rebuild (as best it
can) the array from the four drives? There is nothing wrong with any
of them (even the controller says they are "optimal")
3. If I decide to abandon the idea of RAID (looking like a good idea
from where I am standing), is there a decent 8 port SATA II controller?

4. Is there a way to use my RAID controller as a simple SATA II
controller w/o RAID. That way if something does go wrong, I can use
one of the zillion or so software tools to try and recover something.
Now I basically have no options that I can see.

Any insight would be greatly appreciated.
-Jeff

System specs:

Tyan K8WE (s2895) motherboard
Dual Opteron 285 CPUs (dual core)
4 GB RAM (registered ECC)
Sound Blaster X-Fi sound card
XFX 7900 GTX Video card

Adaptec 2820SA Raid Controller (SATA II)
Western Digital WD5000YS 500 GB SATA II drives (4 drives)
External housing and multilane cable

 

[Mike Tomlinson]

Adaptec 2820SA Raid Controller (SATA II)

Oh dear.

Western Digital WD5000YS 500 GB SATA II drives (4 drives)
External housing

How hot do the drives get?
What's the enclosure make and model? Is the PSU in it sufficient to run
four 500GB drives?

 

[jeff22]

The enclosure came from PC-pitstop. The drives appear to be running
very cool. Also, the problem happened at a time when they were largely
inactive. If it were heat / power I would suspect that when I loaded
the data to the drives would have been a more likely time for failure.

I am just about ready to move the drives internal (scrapping the
housing / psu and cables) but I really liked the idea that the drives
(and their inherent heat) were kept out of the chassis.

Someone suggested the drives might be taking too long on an error and
timing out the controller, but these drives have TLER and thus aren't
supposed to cause such problems for RAID.

-Jeff