Bad magic number in super-block

Thomas Watt tango at
Wed Oct 3 03:30:46 UTC 2007

Hi Nickel Cadmium,

First, try running the command (as root): fdisk -l

That should confirm whether /dev/sdb1 is a valid filesystem partition and not a 
swap partition.  Look for an ID of 83 which identifies valid filesystem partitions.  A partition with ID of 82 is usually swap and won't have a superblock.

That said, if /dev/sdb1 is not a valid filesystem partition, then choose one
that with an ID of 83 and looks like it has the majority of space.  Then you
should be able to use: dumpe2fs -h /dev/sdb2, for example, and see if you get 
any other errors or can then successfully mount the partition.

Sometimes after a reboot, the fdisk -l command reports partitions not in
partition table order and will assign different partition names than the ones
you may normally see to the disk/partition of interest.

-- Tom

More information about the Ext3-users mailing list