On Sun, Jan 27, 2013 at 08:26:56PM +0100, Wolfgang Denk wrote:
[...]

# cat /sys/block/md0/md/mismatch_cnt
362732152


This is with mdadm v3.2.6 (mdadm-3.2.6-7.fc18.x86_64); except for the
huge values of mismatch_cnt, I see no other indications for errors on
the disk drives, RAID arrays or the file systems on top of these.

Is this some known (and hopefully harmless), issue, or must I worry
about our data?

[...]


Hi Wolfgang,

I would shamelessly suggest to try "raid6check", in order
to see if some components have problems.

The software is somehow buried into "mdadm" source code,
probably you'll need to take it from the repository.

Hope it will help,

bye,

-- 

piergiorgio