Boot with bad superblock in root fs

[Jay Cliburn]

Jeff Vian wrote:
> On Sun, 2006-08-27 at 20:49 -0500, Jay Cliburn wrote:
>> Charles Curley wrote:
>>> On Sun, Aug 27, 2006 at 07:57:19PM -0500, Jay Cliburn wrote:
>>>> Is it possible to boot a Linux system that has suffered unfixable 
>>>> primary superblock corruption in the root filesystem (ext2)?  I know the 
>>>> mount command can be supplied an alternate superblock with the sb 
>>>> option, but AFAIK, the earliest this can be done is by setting the 
>>>> option for the failing partition in /etc/fstab.  But of course, root 
>>>> must already be mounted for that to apply.
>>>>
>>>> Is there any Way to specify an alternate superblock to initrd to mount 
>>>> the root filesystem?
>>> Can you boot to a live CD, fix the errant partition, and then reboot?
>>> Finnix should do you.
>> Actually, the problem isn't with my system, but with that of an 
>> acquaintance, and no, the primary superblock refuses to be fixed with 
>> e2fsck -b executed from Ubuntu LiveCD.
>>
> 
> Maybe you can use one of the alternate superblocks when running e2fsck
> on that filesystem.  After all, that is why they are there.
> 

That's what e2fsck -b does.