стереть подпись с устройства (wipe a signature from a device)
Имя (Name)
wipefs - wipe a signature from a device
Синопсис (Synopsis)
wipefs [options] device...
wipefs [--backup] -o offset device...
wipefs [--backup] -a device...
Описание (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 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. This
feature can be used to wipe content on partitions devices as well
as partition table on a disk device, for example by wipefs -a
/dev/sdc1 /dev/sdc2 /dev/sdc.
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 detected.
When option -a is used, all magic strings that are visible for
libblkid(3) 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.
Параметры (Options)
-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.
--lock[=mode]
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(2) 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.
Окружение (Environment)
LIBBLKID_DEBUG=all
enables libblkid(3) debug output.
LOCK_BLOCK_DEVICE=<mode>
use exclusive BSD lock. The mode is "1" or "0". See --lock
for more details.
Примеры (Examples)
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
signature.
dd if=~/wipefs-sdb-0x00000438.bak of=/dev/sdb seek=$0x00000438
bs=1 conv=notrunc
Restores an ext2 signature from the backup file
~/wipefs-sdb-0x00000438.bak.
