superblock
The block at the start of a file system that records its size, layout and state; ext4 keeps backup copies further into the disk.
In more detail
When e2fsck reports a bad magic number in the superblock, mke2fs -n with the original options lists the backup locations without writing, and e2fsck -b uses one. The repair then rewrites the primary copy from the backup.
Related terms
- ext4 — The default filesystem on many Linux distributions, a journaling filesystem that stores files in blocks tracked by inodes.
- fsck — The family of tools that check and repair a file system that is not mounted.
Taught in
- Which RAID, Which File System? Disks That Fail And Inodes That Run Out — CompTIA Linux+ (XK0-006) Exam Prep
- No Space Left, Says The Disk With Room To Spare: Inodes, Held Files, Corruption And Repair — CompTIA Linux+ (XK0-006) Exam Prep
- File System Integrity: Measure, Check, Repair — LPIC-1 Linux Administrator (101-500 and 102-500) Exam Prep