virt-format(1)

1virt-format(1)              Virtualization Support              virt-format(1)
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NAME

6       virt-format - Erase and make a blank disk
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SYNOPSIS

9        virt-format [--options] -a disk.img [-a disk.img ...]
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WARNING

12       Using "virt-format" on live virtual machines, or concurrently with
13       other disk editing tools, can be dangerous, potentially causing disk
14       corruption.  The virtual machine must be shut down before you use this
15       command, and disk images must not be edited concurrently.
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DESCRIPTION

18       Virt-format takes an existing disk file (or it can be a host partition,
19       LV etc), erases all data on it, and formats it as a blank disk.  It can
20       optionally create partition tables, empty filesystems, logical volumes
21       and more.
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23       To create a disk containing data, you may be better to use
24       virt-make-fs(1).  If you are creating a blank disk to use in
25       guestfish(1), you should instead use the guestfish -N option.
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27       Normal usage would be something like this:
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29        virt-format -a disk.qcow
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31       or this:
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33        virt-format -a /dev/VG/LV
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35       disk.qcow or /dev/VG/LV must exist already.  Any data on these disks
36       will be erased by these commands.  These commands will create a single
37       empty partition covering the whole disk, with no filesystem inside it.
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39       Additional parameters can be used to control the creation of
40       partitions, filesystems, etc.  The most commonly used options are:
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42       --filesystem=[ext3|ntfs|vfat|...]
43           Create an empty filesystem ("ext3", "ntfs" etc) inside the
44           partition.
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46       --lvm[=/dev/VG/LV]
47           Create a Linux LVM2 logical volume on the disk.  When used with
48           --filesystem, the filesystem is created inside the LV.
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50       For more information about these and other options, see "OPTIONS"
51       below.
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53       The format of the disk is normally auto-detected, but you can also
54       force it by using the --format option (q.v.).  In situations where you
55       do not trust the existing content of the disk, then it is advisable to
56       use this option to avoid possible exploits.
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OPTIONS

59       --help
60           Display brief help.
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62       -a file
63       --add file
64           Add file, a disk image, host partition, LV, external USB disk, etc.
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66           The format of the disk image is auto-detected.  To override this
67           and force a particular format use the --format=.. option.
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69           Any existing data on the disk is erased.
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71       -a URI
72       --add URI
73           Add a remote disk.  See "ADDING REMOTE STORAGE" in guestfish(1).
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75       --filesystem=ext3|ntfs|vfat|...
76           Create an empty filesystem of the specified type.  Many filesystem
77           types are supported by libguestfs.
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79       --filesystem=none
80           Create no filesystem.  This is the default.
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82       --format=raw|qcow2|..
83       --format
84           The default for the -a option is to auto-detect the format of the
85           disk image.  Using this forces the disk format for -a options which
86           follow on the command line.  Using --format with no argument
87           switches back to auto-detection for subsequent -a options.
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89           For example:
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91            virt-format --format=raw -a disk.img
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93           forces raw format (no auto-detection) for disk.img.
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95            virt-format --format=raw -a disk.img --format -a another.img
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97           forces raw format (no auto-detection) for disk.img and reverts to
98           auto-detection for another.img.
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100           If you have untrusted raw-format guest disk images, you should use
101           this option to specify the disk format.  This avoids a possible
102           security problem with malicious guests (CVE-2010-3851).
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104       --label=LABEL
105           Set the filesystem label.
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107       --lvm=/dev/VG/LV
108           Create a Linux LVM2 logical volume called /dev/VG/LV.  You can
109           change the name of the volume group and logical volume.
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111       --lvm
112           Create a Linux LVM2 logical volume with the default name
113           (/dev/VG/LV).
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115       --lvm=none
116           Create no logical volume.  This is the default.
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118       --partition
119           Create either an MBR or GPT partition covering the whole disk.  MBR
120           is chosen if the disk size is < 2 TB, GPT if ≥ 2 TB.
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122           This is the default.
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124       --partition=gpt
125           Create a GPT partition.
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127       --partition=mbr
128           Create an MBR partition.
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130       --partition=none
131           Create no partition table.  Note that Windows may not be able to
132           see these disks.
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134       -v
135       --verbose
136           Enable verbose messages for debugging.
137
138       -V
139       --version
140           Display version number and exit.
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142       --wipe
143           Normally virt-format does not wipe data from the disk (because that
144           takes a long time).  Thus if there is data on the disk, it is only
145           hidden and partially overwritten by virt-format, and it might be
146           recovered by disk editing tools.
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148           If you use this option, virt-format writes zeroes over the whole
149           disk so that previous data is not recoverable.
150
151       -x  Enable tracing of libguestfs API calls.
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EXIT STATUS

154       This program returns 0 on success, or 1 on failure.
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AUTHOR

161       Richard W.M. Jones http://people.redhat.com/~rjones/
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COPYRIGHT

164       Copyright (C) 2012 Red Hat Inc.
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LICENSE

167       This program is free software; you can redistribute it and/or modify it
168       under the terms of the GNU General Public License as published by the
169       Free Software Foundation; either version 2 of the License, or (at your
170       option) any later version.
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172       This program is distributed in the hope that it will be useful, but
173       WITHOUT ANY WARRANTY; without even the implied warranty of
174       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
175       General Public License for more details.
176
177       You should have received a copy of the GNU General Public License along
178       with this program; if not, write to the Free Software Foundation, Inc.,
179       51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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BUGS

182       To get a list of bugs against libguestfs, use this link:
183       https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
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185       To report a new bug against libguestfs, use this link:
186       https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
187
188       When reporting a bug, please supply:
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190       ·   The version of libguestfs.
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192       ·   Where you got libguestfs (eg. which Linux distro, compiled from
193           source, etc)
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195       ·   Describe the bug accurately and give a way to reproduce it.
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197       ·   Run libguestfs-test-tool(1) and paste the complete, unedited output
198           into the bug report.
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202libguestfs-1.38.2                 2018-05-15                    virt-format(1)