Question 1

What does e2fsck do?

Accepted Answer

Check ext2/3/4 filesystems Checks and repairs ext filesystems. Always run on unmounted devices.

Question 2

Is e2fsck dangerous?

Accepted Answer

HIGH risk. Running fsck on a mounted filesystem can corrupt it; repairs can delete data. Never run on a mounted filesystem (except -n). Take an image backup (dd/ddrescue) of failing disks before repairing. Repairs can move data to lost+found.

Question 3

How can I use e2fsck more safely?

Accepted Answer

e2fsck -n — Read-only check first ddrescue image.img map — Image a failing disk first

Flag	Meaning
`-n`	Read-only check
`-p`	Automatic safe repairs
`-f`	Force check
`-y`	Answer yes to all repairs⚠ May delete or truncate damaged files.