wipefs(8)

1WIPEFS(8)                    System Administration                   WIPEFS(8)
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NAME

6       wipefs - wipe a signature from a device
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SYNOPSIS

9       wipefs [-ahnpqtV] [-o offset] device...
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DESCRIPTION

12       wipefs  can erase filesystem, raid or partition-table signatures (magic
13       strings) from the specified device to make the signatures invisible for
14       libblkid.
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16       wipefs does not erase the filesystem itself nor any other data from the
17       device.  When used without options -a  or  -o,  it  lists  all  visible
18       filesystems and the offsets of their basic signatures.
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20       wipefs  calls BLKRRPART ioctl when erase partition table to inform ker‐
21       nel about the change.
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23       Note that some filesystems or some partition tables  store  more  magic
24       strings on the devices.  The wipefs command lists only the first offset
25       where a magic string has been detected.  The device is not scanned  for
26       additional  magic strings for the same filesystem.  It is possible that
27       after wipefs -o offset the same  filesystem  or  partition  table  will
28       still be visible by another magic string on another offset.
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30       When  used  with option -a, all magic strings that are visible for lib‐
31       blkid are erased.
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33       Note that by default wipefs does not erase nested partition  tables  on
34       non-whole disk devices. The option --force is required.
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OPTIONS

38       -a, --all
39              Erase  all  available  signatures.  The set of erased signatures
40              can be restricted with the -t list option.
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42       -f, --force
43              Force erasure, even if  the  filesystem  is  mounted.   This  is
44              required  in  order  to  erase  the  partition  table on a block
45              device.
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47       -h, --help
48              Print help and exit.
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50       -n, --no-act
51              Causes everything to be done except for the write() call.
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53       -o, --offset offset
54              Specify the location (in bytes) of the signature which should be
55              erased  from  the  device.  The offset number may include a "0x"
56              prefix; then the number will be interpreted as a hex value.   It
57              is possible to specify multiple -o options.
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59              The  offset  argument may be followed by the multiplicative suf‐
60              fixes KiB (=1024), MiB (=1024*1024), and so  on  for  GiB,  TiB,
61              PiB,  EiB,  ZiB  and YiB (the "iB" is optional, e.g. "K" has the
62              same  meaning  as  "KiB"),  or  the  suffixes  KB  (=1000),   MB
63              (=1000*1000), and so on for GB, TB, PB, EB, ZB and YB.
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65       -p, --parsable
66              Print  out  in parsable instead of printable format.  Encode all
67              potentially unsafe characters of a string to  the  corresponding
68              hex value prefixed by '\x'.
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70       -q, --quiet
71              Suppress output messages after successful signature wipe.
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73       -t, --types list
74              Limit  the  set  of printed or erased signatures.  More than one
75              type may be specified in a comma-separated list.   The  list  or
76              individual  types can be prefixed with 'no' to specify the types
77              on which no action  should  be  taken.   For  more  details  see
78              mount(8).
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80       -V, --version
81              Output version information and exit.
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AUTHOR

84       Karel Zak <kzak@redhat.com>
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ENVIRONMENT

87       Setting LIBBLKID_DEBUG=0xffff enables debug output.
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AVAILABILITY

93       The  wipefs  command is part of the util-linux package and is available
94       from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
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98util-linux                       October 2009                        WIPEFS(8)