bad superblock

[Gonzalo Tipola]

Dear Admins,
I have a box with HP-UX 10.00, that gives the following error at boot time:

/dev/vg00/lvol1: BAD SUPER BLOCK: MAGIC NUMBER WRONG

USE -b OPTION TO FSCK TO SPECIFY LOCATION OF AN ALTERNATE

SUPER-BLOCK TO SUPPLY NEEDED INFORMATION; SEE fsck

Then, I tried to run the following command:

bcheckrc# fsck â F hfs â b 16 /dev/vg00/rlvol1

but this it was not successful.

In the file /var/adm/sbtab there is not entry for /dev/adm/rlvol1.

Some suggestion to recover this system.


TIA

Gonza

[Steven E. Protter]

Script:

#!/usr/bin/sh
# /dev/vg01/rlvol2 example
echo "A files system check on parameter 1 is commencing\n"
fsck -F vxfs -o full -y $1

If that doesn't work, you're looking at Ignite recovery(make_tape_recovery).

SEP

[Michael Steele_2]

For HFS file systems CAT out /etc/sbtab and select one of the 100 or so numbers under /stand. They should all be a power a 2. Then use this version of 'fsck':

# fsck -F hfs -b #### /stand

[Suresh Patoria]

Hi,

First start the system in single user mode

then open the /var/adm/sbtab

use anyone of those number

with fsck command

#fsck -F hfs -b <> -o full /dev/vg00/rlvol1

Thanx

[T G Manikandan]

you can check /etc/sbtab for the alternate super block

#fsck -F hfs -b 16 /dev/vg00/lvol1

Just try using lvol1 instead of rlvol1

[Bill Hassell]

Generally, when the alternate superblock 16 does not work, the filesystem has been trashed beyond repair. Time to get the backup tapes.

[Bruno Ganino]

#fsck -g
It fix problems without risk of data loss (bad free list, dirty superblock,etc.).
If any serious damage is encountered that cannot be repaired without risk of data loss, it terminates with a warning message.

Bruno

[George Petrides_1]

I agree with Bill, who's comment is great for all the newbies who claim "Who does tape backups anymore? Just disk backups are fine!"
George