Boot Rescue: Repair the fstab That Dropped You to Emergency Mode

MediumRHCSA Prep15-25 min

The brief

A bad /etc/fstab sent the box to emergency mode. The /data entry is broken three ways — fix it so the system boots cleanly:

1. Wrong device — it points at /dev/sdb1, which no longer exists; the data disk is now /dev/sdc1, and device names aren't stable. Mount it by its UUID (from blkid).

2. Wrong fstype — it says ext2 but the filesystem is ext4.

3. Not resilient — add `nofail` so a missing data disk can't wedge boot again.

The disk's UUID is in /root/case/blkid.txt. Grading reads /etc/fstab (it does not mount anything). See /root/brief.txt.

What you'll do

Repair a broken /etc/fstab that blocks boot
Mount by UUID instead of an unstable device name
Use nofail so a missing non-root disk can't drop the system to emergency mode

Hands-on lab: you work on a real Linux box in your browser, graded on the machine's actual state.