WIPEFS(8) System Administration WIPEFS(8)NAMEwipefs - wipe a signature from a device
SYNOPSISwipefs [-ahnpqtV] [-o offset] device...
DESCRIPTIONwipefs 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.
OPTIONS-a, --all
Erase all available signatures. The set of erased signatures
can be restricted with the -t list option.
-b, --backup
Create a signature backup to the file $HOME/wipefs-<dev‐
name>-<offset>.bak. For more details see EXAMPLES section.
-f, --force
Force erasure, even if the filesystem is mounted. This is
required in order to erase the partition table on a block
device.
-h, --help
Display help text and exit.
-n, --no-act
Causes everything to be done except for the write() call.
-o, --offset offset
Specify the location (in bytes) of the signature which should be
erased from the device. The offset number may include a "0x"
prefix; then the number will be interpreted as a hex value. It
is possible to specify multiple -o options.
The offset argument may be followed by the multiplicative suf‐
fixes KiB (=1024), MiB (=1024*1024), and so on for GiB, TiB,
PiB, EiB, ZiB and YiB (the "iB" is optional, e.g. "K" has the
same meaning as "KiB"), or the suffixes KB (=1000), MB
(=1000*1000), and so on for GB, TB, PB, EB, ZB and YB.
-p, --parsable
Print out in parsable instead of printable format. Encode all
potentially unsafe characters of a string to the corresponding
hex value prefixed by '\x'.
-q, --quiet
Suppress output messages after successful signature wipe.
-t, --types list
Limit the set of printed or erased signatures. More than one
type may be specified in a comma-separated list. The list or
individual types can be prefixed with 'no' to specify the types
on which no action should be taken. For more details see
mount(8).
-V, --version
Display version information and exit.
EXAMPLESwipefs--all --backup /dev/sdb
Erases all signatures from the device /dev/sdb and creates a
signature backup file ~/wipefs-sdb-<offset>.bak for each signa‐
ture.
dd if=~/wipefs-sdb-0x00000438.bak of=/dev/sdb seek=$((0x00000438)) bs=1
conv=notrunc
Restores ext2 signature from the backup file ~/wipefs-
sdb-0x00000438.bak.
AUTHOR
Karel Zak <kzak@redhat.com>
ENVIRONMENT
Setting LIBBLKID_DEBUG=0xffff enables debug output.
SEE ALSOblkid(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)
