"Guessing" superblock parameters

[Andreas Dilger]

On May 01, 2006  03:51 +0200, Niki Hammler wrote:
> And now the important question: Even if I would find a few inodes, they 
> are useless, unless I know the addresses of the inode tables for each 
> block group.
> Is there a way to reconstruct/guess the superblock parameters (block 
> groups, inode tables, ...) if I have the the exact size of the partition 
> and the block size (4096)? I also know that I've taken the default 
> parameters for mke2fs.
> 
> Is the filesystem (offset of inode tables, ...) the same everytime I 
> format the same partition? If not, why?

Yes, this is generally true for a given blocksize.  Even the journal
is created after the inode tables are allocated.  However, as part of
the mke2fs the inode tables are zeroed, so this would in fact be bad
in your case.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.