I'm on Ubuntu 16, and I'm trying to repair my startup disk. I have followed the instructions here, but once I'm at the root access of Recovery mode, it still says that the disk is mounted and it can't run.
If I try
sudo fsck -f /dev/sda3, it just replies:
fsck from util-linux.
Anyone know why it might do that? According to this question, when fsck reports this command, you have to use fsck.ext4. However, when I do that, I still get a message about the volume being in use.
I see there's another question about this on Ubuntu 18, but there's no answer.
Most answers suggest using a Live Disk, but Etcher isn't working on MacOS at the moment, and it's surely not unreasonable to get this done from the recovery command prompt.
It's a vanilla Ubuntu install on a Dell Inspiron laptop.
umount /dev/sda3 gives me "/dev/sda3 not mounted."
fsck.ext4 -f /dev/sda3 gives me "/dev/sda3 is in use".
The output of lsblk /dev/sda gives:
sda disk sda2 part sda3 part ubuntu--vg-root lvm / sda1 part
(obviously, I'm typing this in on another computer) I've left out the sizes, hope that's clear.
I've also tried
umount -lf /. After doing that, when I run
fsck, I get a message that it cannot check if the filesystem is mounted due to missing mtab file.