[linux-lvm] Recovering data from a damaged LVM partition?

[linux-lvm] Recovering data from a damaged LVM partition?

[Shawn]

First post to this list, so please forgive me if I'm not on topic, or 
repeating a common issue.

I have been asked to try to get data from a drive with a damaged partition.  
In the past I've done this with ddrescue, and then mounted the resulting 
image file.  That's not working in this case because the partition in 
question was part of an LVM volume.

My experience with LVM is not that great, as I've never seen a need for it on 
my systems.  But, I've installed the LVM tools, and modified my kernel for 
LVM support, and can at least see the volume on the damaged drive now.  But I 
want to focus on the image file, not the drive.

So, the question is how to mount an image file of an LVM partition?  Anytime I 
try the mount command, it's complaining about the file system type.  I've 
tried the different options for the -t argument, (and am using the -o loop as 
well).

I'm hesitant to run any of the LVM commands to create a volume set, or 
intialize a partition, for fear of loosing the data.  (though I could run 
ddrescue again I suppose, as long as I don't touch the source drive).

Does anyone have any experience here they'd care to share?  Thanks.

BTW, the disk in question is from a default install of Fedora Core 4, and the 
system only had a single drive.  So LVM probably wasn't needed in this case, 
but the person that installed the system is not comfortable with the file 
system details.

Shawn

Re: [linux-lvm] Recovering data from a damaged LVM partition?

[Shawn]

I managed to work out a method to recover the lost data.  I've documented this 
on my blog (http://grover.open2space.com/node/17), for anyone who may be 
facing a similar problem.

Of course, I'm sure those more experienced with LVM may have suggestions, and 
I'd be happy to hear them.  The solution basically meant learning more about 
LVM in general.

Shawn

On Thursday 06 April 2006 15:45, Shawn wrote:
> First post to this list, so please forgive me if I'm not on topic, or
> repeating a common issue.
>
> I have been asked to try to get data from a drive with a damaged partition.
> In the past I've done this with ddrescue, and then mounted the resulting
> image file.  That's not working in this case because the partition in
> question was part of an LVM volume.
>
> My experience with LVM is not that great, as I've never seen a need for it
> on my systems.  But, I've installed the LVM tools, and modified my kernel
> for LVM support, and can at least see the volume on the damaged drive now. 
> But I want to focus on the image file, not the drive.
>
> So, the question is how to mount an image file of an LVM partition? 
> Anytime I try the mount command, it's complaining about the file system
> type.  I've tried the different options for the -t argument, (and am using
> the -o loop as well).
>
> I'm hesitant to run any of the LVM commands to create a volume set, or
> intialize a partition, for fear of loosing the data.  (though I could run
> ddrescue again I suppose, as long as I don't touch the source drive).
>
> Does anyone have any experience here they'd care to share?  Thanks.
>
> BTW, the disk in question is from a default install of Fedora Core 4, and
> the system only had a single drive.  So LVM probably wasn't needed in this
> case, but the person that installed the system is not comfortable with the
> file system details.
>
> Shawn