"Cannot find file system superblock" error - how to recover?

[Scott I. Remick]

--- Ion-Mihai Tetcu <itetcu at apropo.ro> wrote:
> FSCK_FFS(8)
> 
> NAME
>      fsck_ffs, fsck_ufs -- file system consistency check and interactive
>      repair
> 
> SYNOPSIS
>      fsck_ffs [-BFpfny] [-b block#] [-c level] [-m mode] filesystem ...
> 
> 
> -b      Use the block specified immediately after the flag as the super
>         block for the file system.  Block 32 is usually an alternate
>         super block.

Ah, somehow never knew about fsck_ffs. Now I do :-)

Does it matter that /dev/ad6s1c is UFS2 and not UFS1?

> Try doing a newfs -N and see if using some of the alternatives
> super-blocks in fsck_ufs will help. Note that the alternate superblock
> is no longer always at 32, it depends on the size of the file system.

Whoa, something doesn't seem right. I do:

su-2.05b# newfs -N /dev/ad6s1c
/dev/ad6s1c: 76340.1MB (156344516 sectors) block size 16384, fragment size
2048
        using 416 cylinder groups of 183.77MB, 11761 blks, 23552 inodes.
super-block backups (for fsck -b #) at:
 160, 376512, 752864, 1129216, 1505568, 1881920, 2258272, 2634624, 3010976,
 3387328, 3763680, 4140032, 4516384, 4892736, 5269088, 5645440, 6021792,
 6398144, 6774496, 7150848, 7527200, 7903552, 8279904, 8656256, 9032608,
 9408960, 9785312, 10161664, 10538016, 10914368, 11290720, 11667072,
12043424,
 12419776, 12796128, 13172480, 13548832, 13925184, 14301536, 14677888,
 15054240, 15430592, 15806944, 16183296, 16559648, 16936000, 17312352,
 17688704, 18065056, 18441408, 18817760, 19194112, 19570464, 19946816,
 20323168, 20699520, 21075872, 21452224, 21828576, 22204928, 22581280,
 22957632, 23333984, 23710336, 24086688, 24463040, 24839392, 25215744,
 25592096, 25968448, 26344800, 26721152, 27097504, 27473856, 27850208,
 
And this actually continues for quite a bit. There aren't really that many
copies of the superblock on the drive, right?

> * Depending on the architecture and the media, the superblock may
>  * reside in any one of four places. 

Yeah, a lot more than four...

Haven't tried anything yet. Awaiting expert advice first...

Thanks!

=====
Scott I. Remick   --==--   ICQ: 450152 
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