Re: Help with a little dd damage!

["Mikkel L. Ellertson" <mikkel@xxxxxxxxxxxxxxxx>]

Morgan Read wrote:
> Hi Folks
>
> This post could equally be titled - is there a God?
>
> Yesterday I ran this command:
> [root@morgansmachine DiskBUImagesEtc]# dd if=/dev/sda of=pocketpc.rescue 
> bs=1M count=33
> (No output, just bash history.)
>
> Today I ran these commands:
> [root@morgansmachine DiskBUImagesEtc]# dd if=/dev/sda of=2ndstage.rescue 
> bs=1K count=1280
> 1280+0 records in
> 1280+0 records out
> 1310720 bytes (1.3 MB) copied, 0.0535238 s, 24.5 MB/s
> [root@morgansmachine DiskBUImagesEtc]# chown morgan: ./2ndstage.rescue
> [root@morgansmachine DiskBUImagesEtc]# dd if=zImage-LAB-20060421.htc 
> of=/dev/sda
> 2348+0 records in
> 2348+0 records out
> 1202176 bytes (1.2 MB) copied, 0.117155 s, 10.3 MB/s
> [root@morgansmachine DiskBUImagesEtc]#
>
> Both yesterday and today I should not have used /dev/sda, but should 
> have used /dev/sdc...  Ouch...
>
> Now I seem to have an unallocated partition of some 37.26GB where once 
> existed my carefully constructed laptop hard drive.
>
> Everything seems to be running fine, but I expect if I reboot - I wont! 
>  I guess I've just wiped out my MBR or something close.
>
> So, fingers firmly crossed, have I managed to copy enough of my hard 
> drive with the first two commands to be able to patch back the 
> catastrophic damage I seem to have done with the last command.  Could 
> someone more confident than I give me some instruction:)
>
> Any help desperately welcome.
>
> Regards,
> Morgan.
The first thing I would do is run "fdisk -l 2ndstage.rescue" and 
make sure you didn't overwrite the partition table of the image. If 
you did, then you are probably out of luck. If the image is good, 
you can restore the MBR by using "dd if=2ndstage.rescue of=sda 
bs=512 count=1" You will still have corrupted data at the start of 
the drive.

If your have a separate /boot partition at the start of the drive, 
and you have not updated your kernel, then you can restore the 
entire 2ndstage.rescue file.

Mikkel
--

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

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