Badblocks

badblocks is a Linux utility to check for damaged sectors on a disk drive. It marks these sectors so that they are not used in the future and thus do not cause corruption of data.

When run standalone, badblocks gives a list of blocks with problems. Badblocks is not usually invoked by itself unless you want a list of badblocks on the hard disk. Badblocks is usually invoked as an option of 'e2fsck' - Please refer man page of 'e2fsck' on how this is done. When invoked with 'e2fsck' -- quoting the man page: 'This option causes e2fsck to use badblocks(8) program to do a read-only scan of the device in order to find any bad blocks. If any bad blocks are found, they are added to the bad block inode to prevent them from being allocated to a file or direc- tory. If this option is specified twice, then the bad block scan will be done using a non-destructive read-write test.'

Please check the main pages of 'fsck' and 'badblocks' and for the intrepid techie, this is a good link - [http://smartmontools.sourceforge.net/BadBlockHowTo.txt] . If you are a casual user, this link might be confusing.

Example

badblocks -sv /dev/sdb1