How to run a checkdisk?

Question

I suspect there might be bad sector on a disk. What tool is the best equivalent of the error checking tool of windows?

(I used ext3)

Answer 1

To check for bad sectors check the SMART data, probably the best accessible by launching the Disk Utility (Palimpsest). Even if you don't see any bad blocks there, launch a self-test to be sure.

You can also use badblocks

sudo badblocks -sv /dev/sda

will check the whole disk and print out all bad blocks encountered on /dev/sda.

fsck itself will not help you find bad sectors, worse still, if there are a lot of bad sectors it can damage your data even more. Use it only when the disk is healthy.

Answer 2

fsck - check and repair a Linux file system. Invoke it using

fsck /dev/sda1

where /dev/sda1 is the drive you want to check. See 'man fsck' for more details.

There's also 'badblocks' command which checks a device for, you guessed it, bad blocks.

The drive need to be unmounted when checked, so to check the root partition you need to create a file 'forcefsck' in the root of the partition and reboot. The device will be checked upon the next boot:

sudo touch /forcefsck
sudo reboot

Alternatively, you can boot from a Live CD and run the check from there.