WIPEFS(8)		     System Administration		     WIPEFS(8)



NAME
       wipefs - wipe a signature from a device

SYNOPSIS
       wipefs [-ahnpqtV] [-o offset] device...

DESCRIPTION
       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 options -a  or  -o,  it  lists  all  visible
       filesystems and the offsets of their basic signatures.

       wipefs  calls BLKRRPART ioctl when erase partition table to inform ker-
       nel about the change.

       Note that some filesystems or some partition tables  store  more	 magic
       strings on the devices.	The wipefs command lists only the first offset
       where a magic string has been detected.	The device is not scanned  for
       additional  magic strings for the same filesystem.  It is possible that
       after wipefs -o offset the same	filesystem  or	partition  table  will
       still be visible by another magic string on another offset.

       When  used  with option -a, all magic strings that are visible for lib-
       blkid are erased.

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


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

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

       -h, --help
	      Print help and exit.

       -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 suf-
	      fixes 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 output messages after 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
	      Output version information and exit.

AUTHOR
       Karel Zak <kzak@redhat.com>

ENVIRONMENT
       Setting LIBBLKID_DEBUG=0xffff enables debug output.

SEE ALSO
       blkid(8), findfs(8)

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



util-linux			 October 2009			     WIPEFS(8)