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Date: Fri, 16 Feb 2007 08:47:38 +0100
From: Luca Berra <bluca@comedia.it>
Subject: Re: [linux-lvm] vgdisplay - checksum error - what does it mean?
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On Thu, Feb 15, 2007 at 04:23:33PM +0100, Tomasz Chmielewski wrote:
>Tomasz Chmielewski schrieb:
>>Recently, I used "vgdisplay", and noticed that it gives a "checksum error":
>>
>># vgdisplay
>>   /dev/sda2: Checksum error
....
>>
>>Should I be scared? What does it mean? What should I do about it? I 
>>wouldn't like to loose the data.
>>
>>If it helps, my setup looks like that:
>>
>>HDD1-sda2-\
>>HDD2-sdb2-|__RAID-10--LVM-2
>>HDD3-sdc2-|
>>HDD4-sdd2-/
>>
>>I'm running 2.6.17.8 kernel.
>
...
>
>So this basically means, that LVM was set up on /dev/sda2 some time ago, 
>but it was never removed from there - instead, RAID-10 was set up on 
>that partition?

I don't think so. if sda2 is part of a raid10 md array probably the
beginning sector of the md device maps to the beginning sector of the
real device, hence lvm will find an lvm signature on /dev/sda2.

>Should I do something to fix the things? What?
yes, re-enable md_component_detection in lvm.conf, why did you disable
that?

L.

-- 
Luca Berra -- bluca@comedia.it
        Communication Media & Services S.r.l.
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