hi,

i'm in need of some help to recover data.  please feel fre to give me any 
advice.

HOST OS: Centos 5.5 with Xen 3.4.3 with software RAID 1 and LVM on top of it.
GUEST OS:  NexentaStor CE and Centos 5 Paravirtualization machines.

essentially, this is what happened:

1) Prior

ON HOST

/dev/md1 - software raid 1

lvm on top of /dev/md1 - contained several logical volumes.

2) What happened

ON GUEST 

created a XEN VM of NexentaStor Community Edition on the HOST.  Accidentally 
assigned /dev/md1 instead of /dev/md2.

nexenta create a zpool on top of /dev/md2. it didn't check on whether there was 
an existing linux lvm or anything. 

i create 3 zfs filesystems on top of it.  

ON HOST 

i started copying files to the Nexentastor VM, and then my LVM's disppeared.  
it was writing on top of an existing LVM that wa
s being used.  Once the ZFS encapsulated the /dev/md1 with GPT, linux couldn't 
read the LVM anymore.

3) NOW

i have /dev/md1 which still has the LVM information, but it's encapsulated into 
some GPT container.  Nexenta did something to
it.

dd if=/dev/md1 bs=512 count=255 skip=1 of=/tmp/md1.txt

i looked at /tmp/md1.txt and it shows the lvm informmation along with some 
"binary" type headers intermixed throughout the file.

TRIED

since it is a raid 1, i detached one member to serve as backup.  i can "dd" it 
back to the original condition with the backup
copy of the mirror.

it looks like the original linux lvm which was directly on the top of the 
/dev/md1 (not a partition) is somewhat encapsulated
by what ZFS did with GPT.  

i figure i need to remove the GPT and see if i can't get the LVM to be 
detected.  right now, when i run pvscan, no volumes sho
w up.  when i do an fdisk -l, it complains about not being able to read GPT.

4) HOPE

I just hope to recover what data I can.  I wasn't sure if I should use testdisk 
or some other utility, or send it to some place to recover the data.

Gosh, I wished I didn't fat finger /dev/md1 instead of /dev/md2.  Please any 
suggestion or direction would be very very appreciative.

Thanks,

Gary
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