Can't repair super block, bad magic number


Login or Register for Dates, Times and to Reply

 
Thread Tools Search this Thread
# 1  
Can't repair super block, bad magic number

Hello all,

I have a hard drive that I can't repair.
The drive is WD15EARS - Filesystem ext4 ( not 100% sure )
It's used in a Synology DS110j NAS.

I try to run fsck -p /dev/sdb on the HD and I get this:
Code:
Bad magic number in super-block while trying to open /dev/sdb
/dev/sdb:
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>

Next I get the superblocks with mkfs -n /dev/sdb

It outputs 18 blocks, tried them all with fsck -b and all returned this error:
Code:
fsck 1.39 (29-May-2006)
e2fsck 1.39 (29-May-2006)
fsck.ext2: Bad magic number in super-block while trying to open /dev/sdb

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>

Now I believe the HD has a ext4 fs, I couldn't find any info from the disk it self, but read it from the Synology website.

The OS I'm using is CentOS 5.7 and Ubuntu server 10.04. I also have Windows 7 & XP and Mac 10.6.8 to use as well.

I noticed that CentOS fsck goes up to fsck.ext3 and Ubuntu goes up to fsck.ext4, but both produced the same result.

Well, I'm at a loss here... Any help will be greatly appreciated.

Thank you all.
# 2  
Somehow I don't think they created the filesystem on the whole disk, without any partition information. What does the output of fdisk -l /dev/sdb show?
# 3  
Thanks pludi
it shows
Code:
Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table

---------- Post updated at 09:46 PM ---------- Previous update was at 07:21 PM ----------

Extra info...
Ran fdisk -l in Ubuntu and it returned 2 extra lines...
Code:
I/O size (minimun/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

---------- Post updated at 10:03 PM ---------- Previous update was at 09:46 PM ----------

Quote:
Originally Posted by pludi
Somehow I don't think they created the filesystem on the whole disk, without any partition information. What does the output of fdisk -l /dev/sdb show?

Oh, just to let you know, the OS is based on Linux kernel 2.6 GPL Linux.
The system (NAS) was running for about a year before this happened.

I came across one thread on another website that another person having a similar problem was suggested to try vgscan from the lvm2 package, I'm not sure what that is, but thought I'd add it.
# 4  
That's actually a good hint. Run pvscan (scan for physical volumes with a matching identification), vgscan (search for volume groups on known PVs), and then vgdisplay (show information about known volume groups).

Background: LVM is the logical volume manager used in Linux. What it basically does is collect physical disks into larger volume groups, from which logical volumes can be carved. These behave, as far as the filesystem and up is concerned, like partitions, but are easier to extend and can be given meaningful names.
# 5  
I ran the three and returned this:
Code:
# pvscan
No matching physical volumes found.
# vgscan
Reading all physical volumes. This may take a while...
# vgdisplay

I came across a program called TestDisk, its used to repair partition tables.
I haven't used it yet since it wants to know which partition table the drive uses and I'm not sure. It looks like it analyzes first, then if it finds any, it can make the repairs.

TestDisk - Official
cgsecurity.org/wiki/TestDisk

TestDisk - In use
geekyprojects.com/storage/how-to-repair-a-damaged-partition-table-or-mbr/

Should I use that since lvm didn't return any thing?
Login or Register for Dates, Times and to Reply

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #425
Difficulty: Medium
C# 1.0 was first released in December 2002.
True or False?

10 More Discussions You Might Find Interesting

1. Solaris

Bad magic number error

So we have a new to us v240 server with no OS installed. It has an outdated version of OB and ALOM so before we install the OS we want to update both. We have a DVD with the latest OB patch burned on it. We do the boot cdrom command but receive the Bad Magic Number Error. Does an OS need to... (2 Replies)
Discussion started by: dunkpancakes
2 Replies

2. Solaris

Solaris 8.2 Bad magic number

I'll keep it fairly straight forward. I work with a Solaris server and magically today it decided to take a dump on me. At first it give a long list of files that couldn't be acessed before terminating the boot process and returning to the 'ok' prompt. Booting in single-user mode allowed me to run... (4 Replies)
Discussion started by: Aon
4 Replies

3. Solaris

OpenSolaris 2009 bad magic number

Hi guys, I have a big problem wiht my old Netra T1 200. I want to install OpenSolaris 2009 but there's a problem, I burned the ISO image on a CD-RW and then I tryied to install it on netra, but the setup won't to start and the error is that in the attached image. Thanks for the support and sorry... (5 Replies)
Discussion started by: Ducati87
5 Replies

4. Filesystems, Disks and Memory

Bad super block: Magic number wrong

Whenever i run, # fsck -F ufs /dev/dsk/c0t0d0s7 The following error prompt out:- ** /dev/dsk/c0t0d0s7 BAD SUPER BLOCK: MAGIC NUMBER WRONG USE AN ALTERNATE SUPER-BLOCK TO SUPPLY NEEDED INFORMATION; eg. fsck -o b=# where # is the alternate super block. SEE fsck_ufs(1M). ... (3 Replies)
Discussion started by: beginningDBA
3 Replies

5. Solaris

solaris error BAD SUPER BLOCK

I want mount a disk. I have this error. I'm trying to correct with the superblock but i have the same error. Look my procedure. bash-2.03# fsck -F ufs /dev/rdsk/c0t1d0s0 Alternate super block location: 9423392. ** /dev/rdsk/c0t1d0s0 BAD SUPER BLOCK: MAGIC NUMBER WRONG USE AN ALTERNATE... (1 Reply)
Discussion started by: simquest
1 Replies

6. Filesystems, Disks and Memory

Bad Super Block: Magic Number Wrong

I had a power outage a day ago and when the power came back on my FreeBSD 4.6 webserver had problems. It said it was unable to mount /var and made me start in single user mode and said to run fsck MANUALY. So i did and this is now what i get. www# fsck /dev/ad0s1e ** /dev/ad0s1e BAD SUPER... (4 Replies)
Discussion started by: matthewbane
4 Replies

7. HP-UX

BAD SUPER BLOCK - Run fsck with alternate super block number

Error received when I tried to restore a blank disk with an 'auto recovery' DDS tape via HP-UX recovery system 2.0 onto a 1Gb SCSI. I assumed it would do the setup, wrong. Could someone tell me the procedure to initial disk for recovering files using cpio. The system is a HP-UX 9.04 version on a... (1 Reply)
Discussion started by: admin wanabee
1 Replies

8. Filesystems, Disks and Memory

Bad Magic Number

Dear All, i have a SCSI hard disk drive i'm installing on it solaris 5 and the workstation is sun sparc, i made an image of this H.D using Norton Ghost 6, so i took off the SCSI H.D from the sun workstation and put it on a Compaq server then i booted the server from the Norton Ghost floppy disk... (0 Replies)
Discussion started by: wesweshahaha
0 Replies

9. UNIX for Advanced & Expert Users

bad magic number

Hi, when installing a piece of third part software I get the error "Bad magic number" at one point when it tries to use libraries from the bea tuxedo server. Am I correct that this means that the software is expecting 32bit while I'm on 64bit? Is there a way around it or can it only be solved... (5 Replies)
Discussion started by: rein
5 Replies

10. UNIX for Dummies Questions & Answers

Bad magic number in super-block

I am running mandrake 8.2 and when booting I get the message: e2fschk: Bad magic number in super-block while trying to open /dev/hda8. The superblock could not be read or does not describe a correct ext2 filesystem. If the device is valid and really contains a valid an ext2 filesystem (and... (1 Reply)
Discussion started by: Jay
1 Replies

Featured Tech Videos