On 05/21/2010 12:40 PM, MRK wrote:

On 05/21/2010 04:16 AM, Doug Ledford wrote:

quoted

On 05/20/2010 06:38 PM, Neil Brown wrote:
  

quoted

On Thu, 20 May 2010 17:29:37 -0500
Trey Scarborough[off-list ref]  wrote:

    

quoted

Neil Brown wrote:
      

quoted

On Thu, 20 May 2010 12:02:23 -0500
Trey Scarborough[off-list ref]  wrote:


        

quoted

I have a raid 5 array with 9 disks and I have a mismatch_cnt that
keeps
growing. This is causing file corruption on the underlaying file
systems
as well.  I can copy a group of 100 100mb files and then do a
md5sum on
them and 1-3 will be corrupt. If this is a drive that is bad is there
anyway to run a report on the count per drive that these mismatches
occur. I have run smarttools test and do not see one drive that
stands
out to be causing errors. Could something else be causing these
errors?

           

While a bad drive is certainly a possibility here, this is precisely the
type of failure scenario that would make me suspect bad RAM,
motherboard, or CPU.  So I wouldn't rule those out as possibilities
either.
   

Could the cabling to the drive be causing this? (maybe failing or maybe
it's partly disconnected)
I don't remember at what point Linux is at implementing the checksums
between the controller and the drive.

I don't know.  I'm not up on the SATA signaling details so I don't know
if it uses CRC on the signal, but I suspect it does and a bad cable
would cause failed requests.  But I wouldn't bet my house on it, so I
would ask some SATA gurus.


-- 
Doug Ledford [off-list ref]
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