Re: [Dump-users] Error reported on our backup media !

[Bernhard R. E. <be...@be...>]

Hi,

> ###>  e2fsck -b 8193 /dev/hdc1
> e2fsck 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
> e2fsck: Bad magic number in super-block while trying to open /dev/hdc1
> 
> The superblock could not be read or does not describe a correct ext2
> filesystem.  If the device is valid and it really contains an ext2
> filesystem (and not swap or ufs or something else), then the superblock
> is corrupt, and you might try running e2fsck with an alternate superblock:
>  e2fsck -b 8193 <device>
> 
> ###> e2fsck /dev/hdc1
> e2fsck 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
> /dev/hdc1: clean, 286/5636096 files, 6959659/11257540 blocks

probably there's no superblock copy at block 8193.

<WildGuess>
mke2fs set the sparse_super flag when you brought a filesystem onto
/dev/hdc1. Then you have much less superblock backups and therefore no
copy at block 8193 - but I'm not an ext2fs expert.
Check with tune2fs -l for sparse_super.
</WildGuess>

# /sbin/tune2fs -l /dev/hda5
tune2fs 1.19, 13-Jul-2000 for EXT2 FS 0.5b, 95/08/09
Filesystem volume name:   <none>
Last mounted on:          <not available>
Filesystem UUID:          193bf505-5263-4559-bc71-f9287be7d330
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      filetype sparse_super
Filesystem state:         not clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              262144
Block count:              524112
Reserved block count:     26205
Free blocks:              70291
Free inodes:              168689
First block:              0
Block size:               4096
Fragment size:            4096
Blocks per group:         32768
Fragments per group:      32768
Inodes per group:         16384
Inode blocks per group:   512
Last mount time:          Sun Mar  4 18:49:35 2001
Last write time:          Sun Mar 11 12:14:58 2001
Mount count:              1
Maximum mount count:      20
Last checked:             Sun Mar  4 18:49:12 2001
Check interval:           15552000 (6 months)
Next check after:         Fri Aug 31 19:49:12 2001
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:		  128