Badblocks command

From NetworkStuff

A CLI command available on most some Cisco Extreme F5 BigIP Linux Nokia Blue Coat ProxySG platforms; used to... create, modify, display, administer or delete

Usage Syntax

[options]

Common options include;

• ' -
• ' -
• ' -
• ' -
• ' -

Read-only Test

This is a non-destructive read-only test which can be run on disk even if it contains a mounted filesystem. It simply verifies that each block can be read; it does not test for write errors.

   * sudo badblocks -s -v -c 10240 /dev/sdx
         o -s = show progress
         o -v = verbose mode
         o -c 10240 - check 10K blocks at a time

Read-write Test

This test is non-destructive read-write test which reads each block, writes it, then verifies it. It should not be used on block devices with mounted filesystems as it can lead to filesystem corruption.

   * sudo badblocks -n -s -v -c 10240 /dev/sdx
         o -n = non-destructive read-write mode
         o -s = show progress
         o -v = verbose mode
         o -c 10240 - check 10K blocks at a time

Write-mode Test

Using this command will erase all data on the device so only use it if that is what you want. This will write a few patterns to each block, verifying that each one is written and read correctly.

   * sudo badblocks -w -s -v -c 10240 /dev/sdx
         o -w = destructive write-mode test
         o -s = show progress
         o -v = verbose mode
         o -c 10240 - check 10K blocks at a time

Prepare a disk for encryption

The command will completely erase the data on a disk and replace it with random data. This is often a preferred way to prepare a disk for encryption as it is faster than other methods of filling a disk with random data and serves the purpose of checking the disk for errors before the encryption process.

   * sudo badblocks -w -t random -s -v -c 10240 /dev/sdx
         o -w = destructive write-mode test
         o -t random = write random data onto the disk
         o -s = show progress
         o -v = verbose mode
         o -c 10240 - check 10K blocks at a time

Usage Examples

Usage Notes

Linux Usage Notes

With most Linux or Unix commands;

• Non root users may need to prefix commands with the sudo command, for example: sudo chmod 644 *
• Brief help can be displayed using the -h or --help parameter, for example: chmod --help
• A full command manual can be displayed using the man command followed by the command name, for example: man chmod
• Sometimes 'info' pages are used instead of or to provide more information than man pages; for example: info chmod
• Version information can normally be display using the -v, -V or --version parameter, for example: chmod --version. However, this paramater is also frequently used to display verbose output.

Typical Output

Installation

XXX can be installed or upgraded as follows, depending on your platform;

   * Ubuntu: apt-get install XXX 
   * Fedora Core: yum install XXX 
   * FreeBSD: pkg_add -v -r XXX 

Related Files

The badblocks executable is normally found here: XXX

Related Commands

fsck command

Related Articles

Information on other Linux commands

Information on F5 BigIP commands

Information on Cisco commands

Information on Windows commands

Information on Vyatta commands

Information on Extreme commands

Information on Nortel commands

Information on Zebra commands

Information on Secure Platform commands

Information on Blue Coat SGOS commands

Information on Nokia IPSO commands

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