need to restore deleted partitions, system still running

[Jason Paul Joines]

-------- Original Message --------
Subject: Re: need to restore deleted partitions, system still running
From: Kevin O'Gorman <kogorman at gmail.com>
To: Ubuntu user technical support, not for general discussions 
<ubuntu-users at lists.ubuntu.com>
Date: 2012.04.21.Sat.19:34:40
> 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?
>


     Luckily, the last thing I had done before deleting my partitions 
was to make a good full backup.  I just didn't want to take the time to 
restore 140 GB of data if I could easily save it in running form.  As it 
turned out, parted did the trick and I didn't have to restore from backup.

     I had already tried the rescue function of parted without any 
luck.  When I deleted the partitions I had created one big entire disk 
partition in their place.  I deleted this partition and tried parted 
again.  For each of the first three runs, rescue found a new partition 
and was able to recreate it.  It was never able to rescue the fourth and 
last partition though.  However, I manually created the fourth partition 
using all the remaining space with parted and that worked well.  
Everything was back to normal after a reboot.


Jason
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