freebsd stable - Sep 2006 - ufs - fsck_ffs problem

Hola,

I'm running 6.1, and experiening some problems with my RAID array.  Using a
3ware escalade, some corruption to the file system has occurred during a
power outage.  The raw hardware of the filesystem is fine -- at least as far
as the 3ware device is concerned.

At any rate, I issued:

fsho# fsck_ffs -n -b 160 /dev/da0c
Alternate super block location: 160
** /dev/da0c
** Last Mounted on 
** Phase 1 - Check Blocks and Sizes
fsck_ffs: cannot alloc 2641372856 bytes for inoinfo

I found some code by Einstein:
<http://www.atm.tut.fi/list-archive/freebsd-stable-2005/msg04212.html>
which seems to get past the problem.  But, I'm certainly concerned about the
sanctity of my data, and have committed no suggested changes by the program,
as witnessed below:

Alternate super block location: 160
** /dev/da0c (NO WRITE)
** Last Mounted on
** Phase 1 - Check Blocks and Sizes
UNKNOWN FILE TYPE I=2
CLEAR? no

PARTIALLY ALLOCATED INODE I=62
CLEAR? no

PARTIALLY ALLOCATED INODE I=75
CLEAR? no

PARTIALLY ALLOCATED INODE I=110
CLEAR? no

512903222015925405 BAD I=129
2363463046329258390 BAD I=129
-4878472826699975618 BAD I=129
-3101413049108763758 BAD I=129
-4942707920151290579 BAD I=129
8570194651996646049 BAD I=129
2315016788075931432 BAD I=129
-1520079671300232671 BAD I=129
-8795335986215733707 BAD I=129
-4534688454961916277 BAD I=129
5406555421949755135 BAD I=129
EXCESSIVE BAD BLKS I=129
CONTINUE? yes

PARTIALLY TRUNCATED INODE I=130
SALVAGE? no

.....  and this will go on forever, finding billions of problems.

I'm at a loss.  The file system cannot be that corrupt.  Any advice?

On Tue, Sep 19, 2006 at 01:47:34AM -0400, noctua@bellsouth.net
wrote:
> Alternate super block location: 160
> ** /dev/da0c (NO WRITE)
> ** Last Mounted on
> ** Phase 1 - Check Blocks and Sizes
> UNKNOWN FILE TYPE I=2
> CLEAR? no
If inode 2 is messed up, then you may have lost the root directory
of your filesystem. Repairing it probably won't be a lot of fun.

I'm guessing that the RAID somehow did the wrong thing - this seems
to actually be quite common.

	David.