How to resolve bad magic number in super-block error

Step 2: Perform file system check using “e2fsck”

Just fire command e2fsck -b and answer with “y” in case system asks.

[root@rhel1 ~]# e2fsck -b 32768 /dev/sde1
e2fsck 1.41.12 (17-May-2010)
/dev/sde1 was not cleanly unmounted, check forced.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Free blocks count wrong for group #0 (32192, counted=32191).
Fix<y>? yes

Free blocks count wrong for group #4 (32276, counted=32269).
Fix<y>? yes

Free blocks count wrong (307865, counted=307857).
Fix<y>? yes

Free inodes count wrong for group #0 (7829, counted=7826).
Fix<y>? yes

Free inodes count wrong for group #4 (7840, counted=7833).
Fix<y>? yes

Directories count wrong for group #4 (0, counted=4).
Fix<y>? yes

Free inodes count wrong (78389, counted=78379).
Fix<y>? yes


/dev/sde1: ***** FILE SYSTEM WAS MODIFIED *****
/dev/sde1: 21/78400 files (0.0% non-contiguous), 5402/313259 blocks

Now Try to mount the filesystem in this case “/home” partition.

[root@rhel1 ~]# cat /etc/fstab |grep -i /dev/sde1
/dev/sde1 /home ext4 defaults,usrjquota=aquota.user,jqfmt=vfsv0 1 2
[root@rhel1 ~]#

[root@rhel1 ~]# mount /home
[root@rhel1 ~]# df /home
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sde1 1233308 1880 1168780 1% /home

 

Hence we have successfully resolved “bad magic number in super-block” error in Linux. Also this procedure guarantees protection against data loss.