Check that filesystem and partition table are in a good state?

Question

I just changed around the partition table of an Ubuntu 12.04 Desktop and everything seems to be working fine. I want to perform similar changes on another (more important) system.

The machine boots so I'm guessing everything worked well.

Is there a more comprehensive way to check that the partition table is ok and the filesystem is consistent?

Answer 1

If you have a MBR partition table, you can use fdisk:

sudo fdisk -l

This command will print out the partition table and will also automatically perform some consistency checks. If instead you have a GPT partition table, you can use gdisk (thanks Rod Smith for pointing that out):

sudo gdisk /dev/something

where /dev/something is the path to your disk device file (e.g. /dev/sda). From the gdisk interface you will be able to press v to run consistency checks.

---

About the filesystem, there are many ways to perform the check, the one I prefer is this:

sudo touch /forcefsck

This way, once you reboot the computer, the filesystem is checked for errors. This is a nice way of doing it because you don't need to worry about the dangers of running fsck.

It's worth noting that the file /forcefsck will be automatically deleted as soon as the check has completed.

Answer 2

You can use the fsck command. Make sure to execute the fsck on an unmounted file systems to avoid any data corruption issues.

Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

fsck /dev/sdaX

Make sure to replace the X with you device number.

The following are the possible exit codes for fsck command.

0 – No errors
1 – Filesystem errors corrected
2 – System should be rebooted
4 – Filesystem errors left uncorrected
8 – Operational error
16 – Usage or syntax error
32 – Fsck canceled by user request
128 – Shared-library error

You may also take a look at 10 Linux Fsck Command Examples to Check and Repair Filesystem

^{Source:fsck Man Page}