Re: a way to restore my hd ?

[Guest section DW <dwguest@win.tue.nl>]

On Sat, Apr 21, 2001 at 06:52:01PM +0300, Ville Holma wrote:

> EXT2-fs: #blocks per group too big: 2147516416

> debian:~# e2fsck /dev/hdb7
> e2fsck 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
> Corruption found in superblock.  (frags_per_group = 2147516416).

> debian:~# e2fsck -b -2147450879 /dev/hdb7
> e2fsck 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
> e2fsck: Attempt to read block from filesystem resulted in short read while
> trying to open /dev/hdb7

(1) e2fsck is very good at correcting minor problems. But if something
really bad happened, e2fsck will make matters only worse. If your data
is valuable, keep e2fsck far away. (For example, make a copy with dd
before starting to fiddle with the disk contents.)

(2) No doubt you do not really have a disk with over 2^31 blocks,
so this suggestion from e2fsck is just a bug in e2fsck.
Maybe -b 32768 would have been more successful.

It might be interesting to look at the contents of the superblock
to see what kind of corruption occurred. Bad memory tends to change
a single bit. Here your data suggests more than one corrupted bit.
With disk I/O problems one often sees lots of errors - maybe blocks
with all zeros or all ones, or all data shifted by one or more bits, etc.