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[raj]

does anyone know how to recover or find the superblock info. the recent power crash has done some stuff on my UML.

The /dev/ubda path does not exist anymore. Isn't it supposed to be /dev/ubd/0 ??

I tried pulling up the superblock on a different /dev/udbb and pointed me to 8193. However, it is of no use either.

Can someone help? Thanks.

Regards,
--Raj


(Repair filesystem) 36 # fsck
fsck 1.32 (09-Nov-2002)
e2fsck 1.32 (09-Nov-2002)
fsck.ext3: No such file or directory while trying to open /dev/ubda

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>

(Repair filesystem) 37 #
(Repair filesystem) 44 # backup_sblock=`mke2fs -n /dev/ubdb | tail -2 | grep , | awk -F, '{print $1}'`
mke2fs 1.32 (09-Nov-2002)
(Repair filesystem) 45 # echo $backup_sblock
8193
(Repair filesystem) 46 # fsck
fsck fsck.ext2 fsck.jfs fsck.reiserfs
fsck.cramfs fsck.ext3 fsck.msdos fsck.vfat
(Repair filesystem) 46 # fsck.ext2 -b 8193 /dev/ubdb
e2fsck 1.32 (09-Nov-2002)
fsck.ext2: Bad magic number in super-block while trying to open /dev/ubdb

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>

(Repair filesystem) 47 # fsck.ext2 -b 8193 /dev/ubda
e2fsck 1.32 (09-Nov-2002)
fsck.ext2: No such file or directory while trying to open /dev/ubda

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>

(Repair filesystem) 48 #

[griffinn]

First, make sure the configuration in your control panel is pointing /dev/ubda to the intended filesystem image.

If the /dev/ubda node doesn't exist in the rescue image's /dev directory, you can create it like this: Code: # /bin/mknod -m 660 /dev/ubda b 98 0; chown root.disk /dev/ubda

Then you can do this again to locate the alternative superblock: raj wrote: (Repair filesystem) 44 # backup_sblock=`mke2fs -n /dev/ubdb | tail -2 | grep , | awk -F, '{print $1}'`
Only specifying /dev/ubda instead of /dev/ubdb.