[ltp] Rescue and Recovery data destroyer

Vaclav Stepan linux-thinkpad@linux-thinkpad.org
Wed, 25 Jan 2006 02:14:19 +0100


Hello,

I played a little with boot sector and the things around 
the hidden partition on an R50e. Although interesting,
it resulted in full data loss.

I just hope this may save somebody doing the same mistakes.

There were XP preinstalled and recovery partition at the
end. I wanted dual-boot with recovery partition kept intact.
This was fairly easy - I deleted the Windows partition, 
put there new ones - one big for Windows, one big for Linux,
one for shared data and let the R&R from the hidden 
partition recover the factory configuration (which left 
the Linux partition intact).

Everything in the archives said, that if you install boot-loader
into MBR, you won't be able to use the hidden partition any
more. Ok, I installed GRUB at the beginning of the Linux partition
and set up NT loader to do the dual-booting.

This had beed working great... ...except if I needed to switch
between the systems, I did a sw suspend in Linux (few seconds)
and then had to wait a minute or two for Windows to start.
That was annoying :-)

GRUB found two more bootable partitions - the Windows partition
and the R&R partition at the end of the disk. Wow. Shouldn't
it be possible to put GRUB to MBR and simply boot R&R that way?

I tried booting R&R using GRUB from the Linux partition.
It worked fine. I did a backup of MBR using dd (but just of the
first sector, which was the first mistake) and installed grub
to MBR using 'setup (hd0)' from the GRUB shell.

Well --- it didn't work. Although Windows and Linux were fine,
R&R fails with a mysterious error:
STOP c000021a {Fatal System Error}
The Session Manager Initialization process terminated unexpectedly.
0xc000003a.

So the R&R tools check the MBR for some reason - possibly
there are some diagnostic data stored there?
I copied the original MBR back and found that now the machine
does not boot at all. Even better.

I thought - well, you did a backup using the fantastic R&R today,
it won't hurt to try the recovery procedure. Maybe this will
recover the MBR by the way too.

I started the R&R from CD and told it to do recovery from backup
from a CD/DVD. Fine - it asked whether I wan't to delete files
that were created or changed since the last backup before extracting
the backup data. I thought about it a moment and chose yes, as
it seemed reasonable - it shouldn't touch other partitions, should it?

Well - a PQI window appeared stating something like ,,deleting partition
and so on''. It weeped the partition table and I hold the power button
until off.

After reboot the partition table was damaged - just the first Windows
partition and R&R left there, both non-working.

I let testdisk find the partitions and repaired the partition table.
However, the Windows partition was unusable.
I restarted the recovery process (stating I do NOT want to delete
the changed files). It wonderfully recovered the Windows partition
(not the hidden one) and filled the rest of partition table with
pure garbage (disks up to H:, all unformatted). So the Linux partition
was lost and this time unrecoverably (partly overwritten) and the
R&R partition is not bootable. Fortunately, the shared-data partition
was left intact (although I had to rescue it using testdisk).

Has anybody succesfully and non-destructively used the Rescue
and Recovery for rescuing just one of the partitions from backup?

Uf. That's it.

Vaclav Stepan