Linux
Filesystem
Ext*
dumpe2fs — dump ext2/3/4 filesystem metadata
dumpe2fs displays detailed information about ext2/3/4 filesystems including superblock data, block groups, and feature flags.
What dumpe2fs is good for
- Viewing superblock metadata
- Checking filesystem feature flags
- Inspecting block group layout
- Finding backup superblocks
Run read-only against unmounted filesystems when possible for safety.
10 Practical Examples
2) Show superblock information only
sudo dumpe2fs -h /dev/sdX1
3) Find backup superblocks
sudo dumpe2fs /dev/sdX1 | grep -i superblock
4) Check mount count and last check
sudo dumpe2fs -h /dev/sdX1 | egrep 'Mount count|Last checked'
5) View block size and inode size
sudo dumpe2fs -h /dev/sdX1 | egrep 'Block size|Inode size'
6) View filesystem features
sudo dumpe2fs -h /dev/sdX1 | grep -i features
7) Inspect block group layout
sudo dumpe2fs /dev/sdX1 | less
8) Use alternate superblock (advanced recovery)
sudo dumpe2fs -o superblock=32768 /dev/sdX1
9) Verify UUID
sudo dumpe2fs -h /dev/sdX1 | grep UUID
10) Pair with e2fsck
sudo e2fsck -f /dev/sdX1
sudo dumpe2fs -h /dev/sdX1