NAME¶
virt-format - Erase and make a blank disk
SYNOPSIS¶
virt-format [--options] -a disk.img [-a disk.img ...]
DESCRIPTION¶
Virt-format takes an existing disk file (or it can be a host partition, LV etc),
erases all data on it, and formats it as a blank disk. It can
optionally create partition tables, empty filesystems, logical volumes and
more.
To create a disk containing data, you may be better to use
virt-make-fs(1). If you are creating a blank disk to use in
guestfish(1), you should instead use the guestfish
-N option.
Normal usage would be something like this:
virt-format -a disk.qcow
or this:
virt-format -a /dev/VG/LV
"disk.qcow" or "/dev/VG/LV" must exist already.
Any data
on these disks will be erased by these commands. These commands
will create a single empty partition covering the whole disk, with no
filesystem inside it.
Additional parameters can be used to control the creation of partitions,
filesystems, etc. The most commonly used options are:
- --filesystem=[ext3|ntfs|vfat|...]
- Create an empty filesystem ("ext3",
"ntfs" etc) inside the partition.
- --lvm[=/dev/VG/LV]
- Create a Linux LVM2 logical volume on the disk. When used
with --filesystem, the filesystem is created inside the LV.
For more information about these and other options, see "OPTIONS"
below.
The format of the disk is normally auto-detected, but you can also force it by
using the
--format option (q.v.). In situations where you do not trust
the existing content of the disk, then it is advisable to use this option to
avoid possible exploits.
OPTIONS¶
- --help
- Display brief help.
- -a file
- --add file
- Add file, a disk image, host partition, LV, external
USB disk, etc.
The format of the disk image is auto-detected. To override this and force a
particular format use the --format=.. option.
Any existing data on the disk is erased.
- --filesystem=ext3|ntfs|vfat|...
- Create an empty filesystem of the specified type. Many
filesystem types are supported by libguestfs.
- --filesystem=none
- Create no filesystem. This is the default.
- --format=raw|qcow2|..
- --format
- The default for the -a option is to auto-detect the
format of the disk image. Using this forces the disk format for -a
options which follow on the command line. Using --format with no
argument switches back to auto-detection for subsequent -a options.
For example:
virt-format --format=raw -a disk.img
forces raw format (no auto-detection) for "disk.img".
virt-format --format=raw -a disk.img --format -a another.img
forces raw format (no auto-detection) for "disk.img" and reverts
to auto-detection for "another.img".
If you have untrusted raw-format guest disk images, you should use this
option to specify the disk format. This avoids a possible security problem
with malicious guests (CVE-2010-3851).
- --lvm=/dev/VG/LV
- Create a Linux LVM2 logical volume called
"/dev/VG/ LV". You can change the name of the
volume group and logical volume.
- --lvm
- Create a Linux LVM2 logical volume with the default name
("/dev/VG/LV").
- --lvm=none
- Create no logical volume. This is the default.
- --partition
- Create either an MBR or GPT partition covering the whole
disk. MBR is chosen if the disk size is < 2 TB, GPT if ≥ 2 TB.
This is the default.
- --partition=gpt
- Create a GPT partition.
- --partition=mbr
- Create an MBR partition.
- --partition=none
- Create no partition table. Note that Windows may not be
able to see these disks.
- -v
- --verbose
- Enable verbose messages for debugging.
- -V
- --version
- Display version number and exit.
- --wipe
- Normally virt-format does not wipe data from the disk
(because that takes a long time). Thus if there is data on the disk, it is
only hidden and partially overwritten by virt-format, and it might be
recovered by disk editing tools.
If you use this option, virt-format writes zeroes over the whole disk so
that previous data is not recoverable.
- -x
- Enable tracing of libguestfs API calls.
EXIT STATUS¶
This program returns 0 on success, or 1 on failure.
SEE ALSO¶
guestfs(3),
guestfish(1),
virt-filesystems(1),
virt-make-fs(1),
virt-rescue(1),
virt-resize(1),
<
http://libguestfs.org/>.
AUTHOR¶
Richard W.M. Jones <
http://people.redhat.com/~rjones/>
COPYRIGHT¶
Copyright (C) 2012 Red Hat Inc.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 51 Franklin
Street, Fifth Floor, Boston, MA 02110-1301 USA.