lost a drive?

[Jay Cliburn]

Dave Stevens wrote:
> Quoting Tony Nelson <tonynelson at georgeanelson.com>: 
>  
> Thanks, Tony, see below... 
>  
>> At 3:38 PM -0700 9/23/06, Dave Stevens wrote: 
>>> Quoting Keith <ac7xc1nx at gmail.com>: 
>>   ... 
>>>  >  Obtain the rescue CD, boot without mounting the partition and do a 
>>>  > fsck.ext3 /dev/hd## with the hard drive unmounted. 
>>>  > 
>>>
>>> Thanks but no joy. I get: 
>>>
>>> e2fsck 1.35 (28-Feb-2004) 
>>> e2fsck: Bad magic number in superblock while trying to open /dev/hdb2 
>>> The superblock could not be read or does not describe a correct ext2 
>>> filesystem. 
>>> If the device is valid and it really contains an ext2 filesystem (and not 
>> swap 
>>> or ufs or something else), then the superblock is corrupt and you might try 
>>> running e2fsck with an alternate superblock: 
>>> e2fsck -b 8193 <device> 
>>>
>>> So I've done that and get the same message repeatedly with or without the 
>> -b 
>>> parameter. Are there other alternate superblocks? copies? data recovery 
>>> utilities? 
>>  
>> There are lots of alternate superblocks.  See man e2fsck and man  
>> mke2fs with reference to -b -n. 
>  
> gives this: 
>  
> linux:/sbin # e2fsck -n /dev/hda2 
> e2fsck 1.35 (28-Feb-2004) 
> Couldn't find ext2 superblock, trying backup blocks... 
> e2fsck: Bad magic number in super-block while trying to open /dev/hda2 
>  
> The superblock could not be read or does not describe a correct ext2 
> filesystem.  If the device is valid and it really contains an ext2 
> filesystem (and not swap or ufs or something else), then the superblock 
> is corrupt, and you might try running e2fsck with an alternate superblock: 
>     e2fsck -b 8193 <device> 
>  
> I don't understand the severity of this problem. If my data on the drive is 
> irretrievably lost I will reluctantly reformat, install FC5_64 to replace the 
> FC3 now missing in action and life will carry on. I have a backup of my mail 
> and docs from ten days ago so it won't be a catastrophe. 
>  
> But if the fix is only obscure and not too time consuming I'd rather put in 
> the time to both learn what went wrong and to recover my installation to where 
> it is possible to do a more recent backup at least. 
>  
>  
> I am currently running from a SUSE Linux 9.2 Live CD. In that environment YAST 
> recognizes the partition (hda2, as you may have gathered) as an LVM volume, 
> but that's as far as I get. I think the difficulty with using alternative 
> superblocks is related to the block size and that the alternative superblocks 
> are ?only? applicable to other block sizes. The block size in that partition 
> has always been reported by df and du in 1K increments. 
>  
> Ideas? further suggestions? reading I can do online on this? 

First, unmount the partition.

Then, to find the location of all backup superblocks, run

mke2fs -n /dev/hda2

Pick one, then run

e2fsck -b <your_picked_superblock> /dev/hda2