RAID 1+0

[Chris Dillon]

On Fri, 22 Aug 2003, Tony Holmes wrote:

> I've been running a couple servers using vinum's RAID 5. Last night
> I had 2 of the disks in the RAID set drop dead (the first and last
> physcial drives) killing all the data on the set. This is not the
> first time I've lost all my RAID 5 data due to 2 disks dropping in a
> very short period of time (this is the third time actually).

If this is a SCSI array, and I assume it is, make sure your
termination is correct.  After troubleshooting somebody's white-box
10-drive external array when it would consistently drop disks and new
replacements would again "drop dead" a few days to weeks later, I
noticed the vendor didn't properly terminate either of the two LVD
busses.  I was totally surprised that it worked at all with a
half-terminated bus, but I guess LVD is relatively forgiving compared
to SE busses when it comes to termination.  Once a terminator was put
on the end of each bus (the RAID controller was already terminating
the other end), a drive hasn't dropped out in several months.


-- 
 Chris Dillon - cdillon(at)wolves.k12.mo.us
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