need to restore deleted partitions, system still running

[Kevin O'Gorman]

On Sat, Apr 21, 2012 at 4:52 PM, Jason Paul Joines <jason at joines.org> wrote:
>    I'm using Kubuntu 11.04.  By mistake I just deleted all four of my
> partitions and created one big one.  I wasn't paying attention and thought I
> was working on a USB stick instead of my hard drive.
>
>    At any rate, the system is still running and the kernel is still aware of
> the old partition scheme as it is displayed in /proc/partitions.  It'll be
> hosed at the next reboot though as it'll read the new partition table from
> disk.  Is there any way to restore the original partition table from
> /proc/partitions to disk?

When I lost a hardware RAID controller, I recovered its 8 partitions
by writing a program to help me find them.  I think I'll never again
use hardware RAID -- the speed differences are not important enough.

Just recently, I found that parted(8) has a "rescue" command to help
with exactly this process.  It's probably your best bet.  I've never
used it, but I sure would have if I had known it was there.  The way I
did it, it took days of careful operations making sure I wasn't
further screwing things up.

This may also be a teachable moment for you: how are your backups?

-- 
Kevin O'Gorman, PhD