When the Disk Utility fails to fix your hard disk, you’ll have to turn to one of the big guns. Here’s how you can use fsck to repair your Mac hard disk.
When your computer crashes, there is a chance that your filesystem will get corrupted or damage in the process. It is advisable to do a filesystem check regularly to make sure that it is running properly and free of error. In Linux, there is this powerful command “fsck” that you can use to check and repair your filesystem.