[conspire] partition recovery after accidental dd

[Rick Moen]

Quoting Ehud Kaldor (ehud.kaldor at gmail.com):

> sort of the classic "rm -rf /". has anyone managed to recover a 750GB
> disk after dd-ing ~3.5GB on to it, accidentally? i have testdisk and
> gparted running together trying to find something (hopefully by morning)
> but wanted to know if someone had any other suggestion (or wanted to
> tell me i am in some creek and missing a paddle.
> 
> and ye, as you are probably wondering - i was DD-ing an LMDE image to a
> USB to install from, rebooted but USB was not bootable for some reason,
> rebooted again to main OS and DD-ed again in bash using arrow-up, but
> device enumeration changed and i ended up DD-ing my external drive.
> major bummer.

That's actually a good bit worse than merely doing 'rm -rf /', I'm sorry
to say.  When you dd the drive, you're going to immediately start by
clobbering bitwise the boot sector, partition table, and first
filesystem superblock, and it just keeps getting worse from there.

If TestDesk and PhotoRec don't do much for you, then I doubt that
anything else will, either.

I'm currently DBANing (Darik's Boot and Nuke) a number of old hard
drives, and I didn't even check to see if were possible to configure
DBAN to ignore and not overwrite the host system's hard drive.  I just
physically unplugged that drive for the duration, and booted from CD.