Sponsored Content
Special Forums Hardware Filesystems, Disks and Memory Bad Super Block: Magic Number Wrong Post 302116440 by Bynds on Friday 4th of May 2007 12:22:44 AM
Old 05-04-2007
Solution to problem

Hello to all that find this thread through Google :-)

I had a similar problem with my HDD and FreeBSD saying there was a bad superblock.
I followed the first step of the procedure and discovered (to my relief) the backup superblocks.

Once past this point the next reccomendation was to use fsck -b 160 /dev/"my partition"
This doesn't work as FreeBSD's fsck command doesn't acknowledge the -b flag as valid.

The trick is to use fsck_ffs which *does* recognise the -b flag and takes the appropriate action. i.e. fsck_ffs -b 160 /dev/"my partition"

Second tip (don't flame me for it's obviousness, not everyone is a super sysop). Make sure you are have root access otherwise no errors will be corrected.

Third Tip. If it looks like your filesystem is in a really bad way, look at the -y flag in the man page. i.e. read man fsck_ffs looking for -y :-)

I hope this is usefull for anyone else that has the problem.

Cheers,
Neil S Davenport
 

10 More Discussions You Might Find Interesting

1. 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

2. 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

3. 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

4. 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

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. Solaris

wrong magic number

/pci@if,0/pci@1,1/ide@3/dad@0,0 corrupt label wrong magic number can u plz suggustion me (6 Replies)
Discussion started by: tirupathi
6 Replies

7. 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

8. 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

9. Filesystems, Disks and Memory

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: Bad magic number in super-block while trying to open /dev/sdb /dev/sdb: The superblock... (4 Replies)
Discussion started by: dallasw1983
4 Replies

10. 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
REISERFSCK(8)						      System Manager's Manual						     REISERFSCK(8)

NAME
reiserfsck - The checking tool for the ReiserFS filesystem. SYNOPSIS
reiserfsck [ -aprVy ] [ --rebuild-sb | --check | --fix-fixable | --rebuild-tree | --clean-attributes ] [ -j | --journal device ] [ -z | --adjust-size ] [ -n | --nolog ] [ -B | --badblocks file ] [ -l | --logfile file ] [ -q | --quiet ] [ -y | --yes ] [ -f | --force ] [ -S | --scan-whole-partition ] [ --no-journal-available ] device DESCRIPTION
Reiserfsck searches for a Reiserfs filesystem on a device, replays any necessary transactions, and either checks or repairs the file sys- tem. device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). OPTIONS
--rebuild-sb This option recovers the superblock on a Reiserfs partition. Normally you only need this option if mount reports "read_super_block: can't find a reiserfs file system" and you are sure that a Reiserfs file system is there. But remember that if you have used some partition editor program and now you cannot find a filesystem, probably something has gone wrong while repartitioning and the start of the partition has been changed. If so, instead of rebuilding the super block on a wrong place you should find the correct start of the partition first. --check This default action checks filesystem consistency and reports, but does not repair any corruption that it finds. This option may be used on a read-only file system mount. --fix-fixable This option recovers certain kinds of corruption that do not require rebuilding the entire file system tree (--rebuild-tree). Nor- mally you only need this option if the --check option reports "corruption that can be fixed with --fix-fixable". This includes: zeroing invalid data-block pointers, correcting st_size and st_blocks for directories, and deleting invalid directory entries. --rebuild-tree This option rebuilds the entire filesystem tree using leaf nodes found on the device. Normally you only need this option if the reiserfsck --check reports "Running with --rebuild-tree is required". You are strongly encouraged to make a backup copy of the whole partition before attempting the --rebuild-tree option. Once reiserfsck --rebuild-tree is started it must finish its work (and you should not interrupt it), otherwise the filesystem will be left in the unmountable state to avoid subsequent data corruptions. --clean-attributes This option cleans reserved fields of Stat-Data items. There were days when there were no extended attributes in reiserfs. When they were implemented old partitions needed to be cleaned first -- reiserfs code in the kernel did not care about not used fields in its strutures. Thus if you have used one of the old (pre-attrbutes) kernels with a ReiserFS filesystem and you want to use extented attribues there, you should clean the filesystem first. --journal device , -j device This option supplies the device name of the current file system journal. This option is required when the journal resides on a sep- arate device from the main data device (although it can be avoided with the expert option --no-journal-available). --adjust-size, -z This option causes reiserfsck to correct file sizes that are larger than the offset of the last discovered byte. This implies that holes at the end of a file will be removed. File sizes that are smaller than the offset of the last discovered byte are corrected by --fix-fixable. --badblocks file, -B file This option sets the badblock list to be the list of blocks specified in the given `file`. The filesystem badblock list is cleared before the new list is added. It can be used with --fix-fixable to fix the list of badblocks (see debugreiserfs -B). If the device has bad blocks, every time it must be given with the --rebuild-tree option. --logfile file, -l file This option causes reiserfsck to report any corruption it finds to the specified log file rather than to stderr. --nolog, -n This option prevents reiserfsck from reporting any kinds of corruption. --quiet, -q This option prevents reiserfsck from reporting its rate of progress. --yes, -y This option inhibits reiserfsck from asking you for confirmation after telling you what it is going to do. It will assuem you con- firm. For safety, it does not work with the --rebuild-tree option. -a, -p These options are usually passed by fsck -A during the automatic checking of those partitions listed in /etc/fstab. These options cause reiserfsck to print some information about the specified filesystem, to check if error flags in the superblock are set and to do some light-weight checks. If these checks reveal a corruption or the flag indicating a (possibly fixable) corruption is found set in the superblock, then reiserfsck switches to the fix-fixable mode. If the flag indicating a fatal corruption is found set in the superblock, then reiserfsck finishes with an error. --force, -f Force checking even if the file system seems clean. -V This option prints the reiserfsprogs version and then exit. -r This option does nothing at all; it is provided only for backwards compatibility. EXPERT OPTIONS
DO NOT USE THESE OPTIONS UNLESS YOU KNOW WHAT YOU ARE DOING. WE ARE NOT RESPONSIBLE IF YOU LOSE DATA AS A RESULT OF THESE OPTIONS. --no-journal-available This option allows reiserfsck to proceed when the journal device is not available. This option has no effect when the journal is located on the main data device. NOTE: after this operation you must use reiserfstune to specify a new journal device. --scan-whole-partition, -S This option causes --rebuild-tree to scan the whole partition but not only the used space on the partition. AN EXAMPLE OF USING reiserfsck 1. You think something may be wrong with a reiserfs partition on /dev/hda1 or you would just like to perform a periodic disk check. 2. Run reiserfsck --check --logfile check.log /dev/hda1. If reiserfsck --check exits with status 0 it means no errors were discovered. 3. If reiserfsck --check exits with status 1 (and reports about fixable corruptions) it means that you should run reiserfsck --fix-fixable --logfile fixable.log /dev/hda1. 4. If reiserfsck --check exits with status 2 (and reports about fatal corruptions) it means that you need to run reiserfsck --rebuild-tree. If reiserfsck --check fails in some way you should also run reiserfsck --rebuild-tree, but we also encourage you to submit this as a bug report. 5. Before running reiserfsck --rebuild-tree, please make a backup of the whole partition before proceeding. Then run reiserfsck --rebuild- tree --logfile rebuild.log /dev/hda1. 6. If the reiserfsck --rebuild-tree step fails or does not recover what you expected, please submit this as a bug report. Try to provide as much information as possible including your platform and Linux kernel version. We will try to help solve the problem. EXIT CODES
reiserfsck uses the following exit codes: 0 - No errors. 1 - File system errors corrected. 2 - Reboot is needed. 4 - File system fatal errors left uncorrected, reiserfsck --rebuild-tree needs to be launched. 6 - File system fixable errors left uncorrected, reiserfsck --fix-fixable needs to be launched. 8 - Operational error. 16 - Usage or syntax error. AUTHOR
This version of reiserfsck has been written by Vitaly Fertman <vitaly@namesys.com>. BUGS
Please report bugs to the ReiserFS developers <reiserfs-dev@namesys.com>, providing as much information as possible--your hardware, kernel, patches, settings, all printed messages, the logfile; check the syslog file for any related information. TODO
Faster recovering, signal handling. SEE ALSO
mkreiserfs(8), reiserfstune(8) resize_reiserfs(8), debugreiserfs(8), Reiserfsprogs-3.6.21 January 2009 REISERFSCK(8)
All times are GMT -4. The time now is 02:03 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy