Bug#509523: lvm2: LV is not recognized anymore

[Todd Charron]

Hi all,

I finally resolved my issue here.  In my case, my LVM was on a raid array 
(/dev/md0).  Somewhere along the way a partition table got created on 
/dev/md0.  Newer versions of lvm automatically skip devices with partition 
tables which lead to the LV not being recognized.

I zeroed out the partition table with dd if=/dev/zero of=/dev/md0 bs=512 
count=1 and everything was detected again.

This may be a problem for anyone upgrading from lenny, since 2.02.39 doesn't 
make this check and thus works, but once they upgrade to squeeze they may no 
longer have a working system.

I'm not sure if there's any way to prevent this from biting anyone else when 
they upgrade.  It certainly wasn't a pleasant experience for me.

Thanks.

Todd