[CLOSED] Bad magic number in super-block

[BrotherJ]

Hallo zusammen,

mich hat es heute erwischt, dass meine Maschine mit Debian 10 nicht vollständig booten konnte. Als Problem habe ich eine Festplatte (/dev/sdm) ausgemacht. Wenn ich die jetzt checken will, bekomme ich den Hinweis auf einen defekten Superblock

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 # fsck /dev/sdm
fsck from util-linux 2.33.1
e2fsck 1.44.5 (15-Dec-2018)
ext2fs_open2: Bad magic number in super-block
fsck.ext2: Superblock invalid, trying backup blocks...
fsck.ext2: Bad magic number in super-block while trying to open /dev/sdm

The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem.  If the device is valid and it really contains an ext2/ext3/ext4
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>
 or
    e2fsck -b 32768 <device>

Found a dos partition table in /dev/sdm

und

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e2fsck -b 8193 /dev/sdm
e2fsck 1.44.5 (15-Dec-2018)
e2fsck: Bad magic number in super-block while trying to open /dev/sdm

The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem.  If the device is valid and it really contains an ext2/ext3/ext4
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>
 or
    e2fsck -b 32768 <device>

Found a dos partition table in /dev/sdm

Lässt sich dieser Superblock noch einmal reparieren? Die empfohlene Methode klappt leider wie gezeigt nicht.

Grüße

BrotherJ

[mludwig]

Das wichtige Detail aus deiner Ausgabe war für mich:

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Found a dos partition table in /dev/sdm

Soll heißen das Dateisystem ist dann wohl eher in /dev/sdmX , also sdm1 oder auch sdm5

Edith:
Ausgabe der Partitionstabelle als root:

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fdisk -l /dev/sdm

[schwedenmann]

Hallo

Ev. mal testdisk in Verbindung mit fschk

https://www.cgsecurity.org/wiki/Advance ... SuperBlock


mfg
schwedenmann

[BrotherJ]

Anbei die erste Ausgabe:

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fsck -l /dev/sdm
fsck from util-linux 2.33.1
e2fsck 1.44.5 (15-Dec-2018)
ext2fs_open2: Bad magic number in super-block
fsck.ext2: Superblock invalid, trying backup blocks...
fsck.ext2: Bad magic number in super-block while trying to open /dev/sdm

The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem.  If the device is valid and it really contains an ext2/ext3/ext4
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>
 or
    e2fsck -b 32768 <device>

Found a dos partition table in /dev/sdm

Das ist das Testergebnis:

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Partition table type (auto): Intel
Disk /dev/sdm - 500 GB / 465 GiB - ST3500418AS
Partition table type: Intel

Interface Advanced
Geometry from i386 MBR: head=36 sector=63

LVM2 magic value at 0/32/33
 1 P Linux LVM                0  32 33 60801  80 63  976771120
     LVM2, 500 GB / 465 GiB
Change partition type:
 1 P Linux                    0  32 33 60801  80 63  976771120
     LVM2, 500 GB / 465 GiB
search_superblock

block_group_nr 1

recover_EXT2: "e2fsck -b 32768 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=1/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 262144 (block=32768, blocksize=4096)

block_group_nr 3

recover_EXT2: "e2fsck -b 98304 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=3/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 786432 (block=98304, blocksize=4096)

block_group_nr 5

recover_EXT2: "e2fsck -b 163840 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=5/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 1310720 (block=163840, blocksize=4096)

block_group_nr 7

recover_EXT2: "e2fsck -b 229376 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=7/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 1835008 (block=229376, blocksize=4096)

block_group_nr 9

recover_EXT2: "e2fsck -b 294912 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=9/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 2359296 (block=294912, blocksize=4096)

block_group_nr 25

recover_EXT2: "e2fsck -b 819200 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=25/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 6553600 (block=819200, blocksize=4096)

block_group_nr 27

recover_EXT2: "e2fsck -b 884736 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=27/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 7077888 (block=884736, blocksize=4096)

block_group_nr 49

recover_EXT2: "e2fsck -b 1605632 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=49/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 12845056 (block=1605632, blocksize=4096)

block_group_nr 81

recover_EXT2: "e2fsck -b 2654208 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=81/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 21233664 (block=2654208, blocksize=4096)

block_group_nr 125

recover_EXT2: "e2fsck -b 4096000 -B 4096 device" may be needed
recover_EXT2: s_block_group_nr=125/3726, s_mnt_count=0/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 122096390
recover_EXT2: part_size 976771120
Filesystem created: Thu Aug  6 14:38:31 2020
Ext2 superblock found at sector 32768000 (block=4096000, blocksize=4096)
  Linux                    0  32 33 60801  80 63  976771120
superblock 32768, blocksize=4096 []
superblock 98304, blocksize=4096 []
superblock 163840, blocksize=4096 []
superblock 229376, blocksize=4096 []
superblock 294912, blocksize=4096 []
superblock 819200, blocksize=4096 []
superblock 884736, blocksize=4096 []
superblock 1605632, blocksize=4096 []
superblock 2654208, blocksize=4096 []
superblock 4096000, blocksize=4096 []

To repair the filesystem using alternate superblock, run
fsck.ext4 -p -b superblock -B blocksize device

TestDisk exited normally.

Wenn ich jetzt wie empfohlen versuche zu reparieren, dann bekomme ich das ursprüngle Ergebnis:

Code: Alles auswählen

fsck.ext4 -p -b 32768 -B 4096 /dev/sdm
fsck.ext4 -p -b 98304 -B 4096 /dev/sdm
fsck.ext4 -p -b 163840 -B 4096 /dev/sdm
fsck.ext4 -p -b 229376 -B 4096 /dev/sdm
fsck.ext4 -p -b 294912 -B 4096 /dev/sdm
fsck.ext4 -p -b 819200 -B 4096 /dev/sdm
fsck.ext4 -p -b 884736 -B 4096 /dev/sdm
fsck.ext4 -p -b 1605632 -B 4096 /dev/sdm
fsck.ext4 -p -b 2654208 -B 4096 /dev/sdm
fsck.ext4 -p -b 4096000 -B 4096 /dev/sdm

führt zu

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fsck.ext4: Bad magic number in super-block while trying to open /dev/sdm
/dev/sdm: 
The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem.  If the device is valid and it really contains an ext2/ext3/ext4
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>
 or
    e2fsck -b 32768 <device>

Found a dos partition table in /dev/sdm

[mludwig]

Ich schrieb

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fdisk -l /dev/sdm

da hier die Partitionstabelle ausgegeben wird. fsck ist ein völlig anderes Kommando!

[BrotherJ]

Sorry,

da war ich komplett durcheinander:

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fdisk -l /dev/sdm
Disk /dev/sdm: 465,8 GiB, 500107862016 bytes, 976773168 sectors
Disk model: ST3500418AS     
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000e1bfe

Device     Boot Start       End   Sectors   Size Id Type
/dev/sdm1        2048 976773167 976771120 465,8G 83 Linux

[mludwig]

Nach der Ausgabe dieses Kommandos ist das Dateisystem auf /dev/sdm1, also eher

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mount /dev/sdm1 /mnt/<irgendwas>

bzw.

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fsck /dev/sdm1

Das fsck auf /dev/sdm den Superblock nicht findet macht dann sinn, denn dieser ist ja in /dev/sdm1 (also gleicher Datenträger, aber einige (kilo)bytes versetzt ... Ich hoffe du hast nicht schon drauf rumgeschrieben (also per fsck)

[BrotherJ]

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# mount /dev/sdm1 /mnt/
mount: /mnt: unknown filesystem type 'LVM2_member'.

Das war allerdings früher ein LVM2 Filesystem, das ich vor einer Neunutzung neu formatiert und zuvor mit fdisk den Filetype "83" zugewiesen hatte. Bis gestern lief das ja auch sehr gut und liess sich einhängen.
Okay, ich habe mittlerweile mit fdisk den Type "83" noch einmal neugesetzt.

[BrotherJ]

Ich habe die Platte komplett neu generiert. Zum Glück gab es die Backups.