Can t read the superblock?
There can be several reasons why your OS can’t read the superblock on your HDD.
- The HDD is dropped to the ground and the superblock is damaged. This is usually physical damage to the corresponding sectors on the disk.
- There’s a sudden power outage.
How do I fix superblock?
How to Restore a Bad Superblock
- Become superuser.
- Change to a directory outside the damaged file system.
- Unmount the file system. # umount mount-point.
- Display the superblock values with the newfs -N command. # newfs -N /dev/rdsk/ device-name.
- Provide an alternative superblock with the fsck command.
How do I fix bad magic number in superblock?
- Run fsck -b $BACKUPSB /dev/sda to repair your disk using the Superblock backup. As an example, for the output above you’ll want to run fsck -b 32768 /dev/sda which uses the first backup block.
- Mount the disk with mount -o barrier=0 /dev/sda /media/sda to confirm the disk has been repaired and can now be mounted.
What is a superblock?
Definition of superblock : a very large commercial or residential block barred to through traffic, crossed by pedestrian walks and sometimes access roads, and often spotted with grassed malls.
What is a disk superblock?
A superblock is a record of the characteristics of a filesystem, including its size, the block size, the empty and the filled blocks and their respective counts, the size and location of the inode tables, the disk block map and usage information, and the size of the block groups.
What is stored in the superblock?
How do I fix corrupted ext4 filesystem?
The simplest use case of the fsck command is to repair a non-root corrupted ext3 or ext4 file system.
- If you don’t know the device name, use fdisk , df , or any other tool to find it.
- Unmount the device: sudo umount /dev/sdc1.
- Run fsck to repair the file system: sudo fsck -p /dev/sdc1.