recommendations on how to recover a corrupted, LVM-based hard drive?

[Robert P. J. Day]

On Wed, 12 Feb 2014, Chris Murphy wrote:

>
> On Feb 12, 2014, at 9:39 AM, Robert P. J. Day <rpjday at crashcourse.ca> wrote:
> >
> >
> >  /dev/vg1/home /opt/home     ext4    defaults        1 2
> >
> > so that (obviously) what used to be the "home" logical volume in the
> > old "vg1" volume group appeared under /opt/home, and was available for
> > the occasional restoration of old content.
> >
> >  problem: person was trying to write a 2G bootable (embedded Linux)
> > image to an inserted USB drive and, rather than writing to /dev/sdc
> > (the USB drive), "dd"ed to /dev/sdb instead, overwriting the first 2G
> > of the secondary hard drive and, with it, whatever LSM content resided
> > in that first 2G.
>
> What was the approximate partition scheme of the disk before it was
> overwritten with dd? Typical would be a boot partition first,
> causing the LVM partition to be offset well back from 2MB from the
> start of the disk, in which case pvck can be used to find it.
>
> man pvck

  it was 2G that was overwritten, not just 2M. so i'm quite willing to
believe that it's unrecoverable. but that "testdisk" utility claims to
be finding *something*, so i'll just let it finish and post what it
reports.

  as for disk partitioning, i was told that half the drive was
allocated to a "home" LV, but i have no idea where that would have
started or how badly it would have been corrupted.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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