how to fix a incorrect fstab
If you messed up your fstab you may can’t boot your linux machine. You will need a recovery usb or disk attached to the system, also a dual boot linux will do the job.
Lets say you have missconfigured a fstab entry and the server is looping through the boot loader. You can fix the fstab file after booting from a recovery media with the following commands:
lvm vgscan -v
# this will show your vgs
vgchange -a y ubuntu-vg
# this will activate your vg with the name ubuntu-vg
lvs
# this will list your lvs
mkdir /mnt/mount
mount /dev/mapper/ubuntu-vg/ubuntu-lv /mnt/mount
Now your lv should be mounted and you can edit your fstab file under /mnt/mount/etc/fstab
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