Re: Can't resolve mismatch_count > 0 for a raid 1 array

[Bill Davidsen <davidsen@tmr.com>]

Steven Ellis wrote:
> I've resolved most of my raid issues by re-housing the affected system 
> and replacing the motherboard, but across the 3 boards I've tried I 
> always have an issue with my /dev/md1 array producing mismatch_count 
> of 128 or 256.
>
> System is running Centos 5.2 with a Xen Dom0 kernel
>
> This md1 volume is a pair of 40GB HDs raid1 on an IDE controller which 
> I them have a bunch of LVM's that are my Xen guests.
>
> Is there any chance that these mismatch_count values are due to swap 
> partitions for the Xen guests?

That's the cause, and since md code doesn't currently have a clue which 
copy is "right" it's always a problem if you do something like suspend 
to disk. You probably don't do that with xen images, but swap and raid1 
almost always have a mismatch.

-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc

"You are disgraced professional losers. And by the way, give us our money back."
    - Representative Earl Pomeroy,  Democrat of North Dakota
on the A.I.G. executives who were paid bonuses  after a federal bailout.