Ubuntu – How to use fsck in Ubuntu


I intend to use fsck for checking my Linux partition of the main disk, because its file system is suspicious of being

not unmounted cleanly

by shutting down the system. I have searched in my environment variables: none of them except of PATH should control the fsck program. But the program apparently needs to be used during a boot:

:~$ fsck -V
fsck from util-linux 2.20.1
Checking all file systems.
[/sbin/fsck.ext4 (1) -- /] fsck.ext4 /dev/sda6 
e2fsck 1.42 (29-Nov-2011)
/dev/sda6 is mounted.
WARNING!!! The filesystem is mounted. If you continue you WILL cause SEVERE filesystem damage. Do you really want to continue? no check aborted.

(There is no /forcefsck file in my root according to How do I find out if there will be a fsck during the next boot? . My etc/fstab file contains

# /etc/fstab: static file system information.
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
proc            /proc           proc    nodev,noexec,nosuid 0       0
# / was on /dev/sda6 during installation
UUID=1ac55d8d-c112-4bc7-9e79-921d196f9f79 /               ext4    errors=remount-ro 0       1
# swap was on /dev/sda7 during installation
UUID=54f7e314-50e2-419b-a45d-47c3058ecc00 none            swap    sw              0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto,exec,utf8 0       0

According to an answer to Slow reboot – understanding fsck and tune2fs I have tried tune2fs hoping that I'll get the present value of the


parameter to be able to set it to 1 for checking the partition during the next boot. But after

sudo rm /var/lib/update-notifier/fsck-at-reboot

and a restart I have only got a response

:~$ tune2fs -l /dev/sda6
tune2fs 1.42 (29-Nov-2011)
tune2fs: Permission denied while trying to open /dev/sda6
Couldn't find valid filesystem superblock

Can I use

sudo tune2fs -l /dev/sda6

safely? Thanks.

Best Answer

To run fsck on your harddrive you need to boot a liveCD and then run the commands with your harddrive partitions as the target.

"There is no /forcefsck file in my root"

-You need to create the file, it is just a blank file so run sudo touch /forcefsck and fsck will check your drive next time your reboot.