In regard to: rhelv6-list Digest, Vol 76, Issue 1, rhelv6-list-request redh :
This isn't something we routinely look at, but after
a couple of VMware systems showing scsi errors, I noticed almost
every Redhat 6 system will show some disk errors from
something like fsck -n / or same on /var
# fsck -n /
fsck from util-linux-ng 2.17.2
e2fsck 1.41.12 (17-May-2010)
Warning! /dev/sda1 is mounted.
There's your problem. Don't run fsck on a mounted filesystem. Even
with -n, it just shows you false positives.
Do some web searching for
fsck on a mounted filesystem
to understand why.