ad0: FAILURE - WRITE_DMA

[Mikhail P.]

Hi,

This question probably has been discussed numerous times, but I'm somewhat 
unsure what really causes ATA failures..

I have pretty basic server here which has two IDE drives - each is 200GB. 
System is FreeBSD-5.2.1-p9
That server has been setup about 9 months ago, and just about 3 months ago my 
logs quickly filled up with:
ad0: FAILURE - WRITE_DMA status=51<READY,DSC,ERROR> error=10<NID_NOT_FOUND> 
LBA=268435455

Server was still running, but I was unable to write to certain files/folders 
on the drive - whenever I tried to access $HOME/.fetchmailrc, for example, it 
wouldn't read/write the file and system would fire up a message similar to 
above.
After couple reboots, I started getting more and more of these, and server was 
unusable, so I had to shut down all services and mount drives read only to 
backup data from the drives..

At first, I thought, this could be related to poor cooling of the parts, so 
drives could easily overheat in the long run.

After successful backup, I purchased two new drives, with two aluminum drive 
fans. New drives' models were identical to the old ones -
ad0 <ST3200822A/3.01> ATA/ATAPI rev 6
which is Seagate's 200GB drive.

I reloaded OS on the new drives, then restored all data from the old drives. 
All seemed to be fine for 2 months now... but today I woke up, and noticed 
these messages again.

So now the whole situation leads me to a question - is there some issues with 
the ATA driver/system [or filesystem?] on FreeBSD-5.2.1? What can I do to 
stop these frequent failures? How do I diagnose the drives (and see whether 
it is really a hardware issue or something else) remotely (I don't have local 
access to the server - it is sitting overseas)?
It seems to me that if I continue running system as now, I will have these 
failed drives every 1-2 months! It does not sound like a normal situation.

I am running FreeBSD-5.2.1-p9, filesystem is UFS2, and all partitions [except 
for /] have softupdates "on". Kernel is built on GENERIC, with only added 
ipfw options.


regards,
M.