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 kernel 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 off-
       set where a magic string has been detected.  The device is not scanned for additional magic strings for the same filesystem.  It is  possi-
       ble 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 libblkid are erased.

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" pre-
	      fix; 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 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 individ-
	      ual 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)