mdadm

mismatch_cnt is not 0

Submitted by sandip on Sun, 07/04/2010 - 21:02

Mismatch_cnt (/sys/block/md#/md/mismatch_cnt) is the number of unsynchronized blocks in the raid.

Not much of an issue if this is reported on raid-0 or raid-1 and can be ignored. See bugzilla report: Bug 566828.

The repair is to rebuild the raid:

echo repair >/sys/block/md#/md/sync_action

This does not reset the count, but if you force a check after the rebuild is complete:

echo check >/sys/block/md#/md/sync_action

Count should return to zero. Verify with:

cat /sys/block/md#/md/mismatch_cnt