wipefs(8) — Linux manual page


WIPEFS(8)                   System Administration                  WIPEFS(8)

NAME         top

       wipefs - wipe a signature from a device

SYNOPSIS         top

       wipefs [options] device...

       wipefs [--backup] -o offset device...

       wipefs [--backup] -a device...

DESCRIPTION         top

       wipefs can erase filesystem, raid or partition-table signatures
       (magic strings) from the specified device to make the signatures
       invisible for libblkid.  wipefs does not erase the filesystem itself
       nor any other data from the device.

       When used without any options, wipefs lists all visible filesystems
       and the offsets of their basic signatures.  The default output is
       subject to change.  So whenever possible, you should avoid using
       default outputs in your scripts.  Always explicitly define expected
       columns by using --output columns-list in environments where a stable
       output is required.

       wipefs calls the BLKRRPART ioctl when it has erased a partition-table
       signature to inform the kernel about the change. The ioctl is called
       as the last step and when all specified signatures from all specified
       devices are already erased.

       Note that some filesystems and some partition tables store more magic
       strings on the device (e.g., FAT, ZFS, GPT).  The wipefs command
       (since v2.31) lists all the offset where a magic strings have been

       When option -a is used, all magic strings that are visible for
       libblkid are erased. In this case the wipefs scans the device again
       after each modification (erase) until no magic string is found.

       Note that by default wipefs does not erase nested partition tables on
       non-whole disk devices.  For this the option --force is required.

OPTIONS         top

       -a, --all
              Erase all available signatures.  The set of erased signatures
              can be restricted with the -t option.

       -b, --backup
              Create a signature backup to the file
              $HOME/wipefs-<devname>-<offset>.bak.  For more details see the
              EXAMPLE section.

       -f, --force
              Force erasure, even if the filesystem is mounted.  This is
              required in order to erase a partition-table signature on a
              block device.

       -h, --help
              Display help text and exit.

       -J, --json
              Use JSON output format.

              Use exclusive BSD lock for device or file it operates.  The
              optional argument mode can be yes, no (or 1 and 0) or
              nonblock.  If the mode argument is omitted, it defaults to
              "yes".  This option overwrites environment variable
              $LOCK_BLOCK_DEVICE.  The default is not to use any lock at
              all, but it's recommended to avoid collisions with udevd or
              other tools.

       -i, --noheadings
              Do not print a header line.

       -O, --output list
              Specify which output columns to print.  Use --help to get a
              list of all supported columns.

       -n, --no-act
              Causes everything to be done except for the write() call.

       -o, --offset offset
              Specify the location (in bytes) of the signature which should
              be erased from the device.  The offset number may include a
              "0x" prefix; then the number will be interpreted as a hex
              value.  It is possible to specify multiple -o options.

              The offset argument may be followed by the multiplicative
              suffixes KiB (=1024), MiB (=1024*1024), and so on for GiB,
              TiB, PiB, EiB, ZiB and YiB (the "iB" is optional, e.g., "K"
              has the same meaning as "KiB"), or the suffixes KB (=1000), MB
              (=1000*1000), and so on for GB, TB, PB, EB, ZB and YB.

       -p, --parsable
              Print out in parsable instead of printable format.  Encode all
              potentially unsafe characters of a string to the corresponding
              hex value prefixed by '\x'.

       -q, --quiet
              Suppress any messages after a successful signature wipe.

       -t, --types list
              Limit the set of printed or erased signatures.  More than one
              type may be specified in a comma-separated list.  The list or
              individual types can be prefixed with 'no' to specify the
              types on which no action should be taken.  For more details
              see mount(8).

       -V, --version
              Display version information and exit.

ENVIRONMENT         top

              enables libblkid debug output.

              use exclusive BSD lock.  The mode is "1" or "0".  See --lock
              for more details.

EXAMPLE         top

       wipefs /dev/sda*
              Prints information about sda and all partitions on sda.

       wipefs --all --backup /dev/sdb
              Erases all signatures from the device /dev/sdb and creates a
              signature backup file ~/wipefs-sdb-<offset>.bak for each

       dd if=~/wipefs-sdb-0x00000438.bak of=/dev/sdb seek=$((0x00000438))
       bs=1 conv=notrunc
              Restores an ext2 signature from the backup file  ~/wipefs-

AUTHORS         top

       Karel Zak <kzak@redhat.com>

SEE ALSO         top

       blkid(8), findfs(8)

AVAILABILITY         top

       The wipefs command is part of the util-linux package and is available
       from https://www.kernel.org/pub/linux/utils/util-linux/.

COLOPHON         top

       This page is part of the util-linux (a random collection of Linux
       utilities) project.  Information about the project can be found at 
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.  If you have a
       bug report for this manual page, send it to
       util-linux@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2020-11-01.  (At that time, the date of the most recent commit that
       was found in the repository was 2020-10-21.)  If you discover any
       rendering problems in this HTML version of the page, or you believe
       there is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

util-linux                      December 2014                      WIPEFS(8)

Pages that refer to this page: systemd.mount(5)systemd.swap(5)blkid(8)btrfs-device(8)cfdisk(8)fdisk(8)mkfs.btrfs(8)sfdisk(8)