5 virt-df - Display free space on virtual filesystems
11 virt-df [--options] -d domname
13 virt-df [--options] -a disk.img [-a disk.img ...]
17 virt-df [--options] domname
19 virt-df [--options] disk.img [disk.img ...]
23 C<virt-df> is a command line tool to display free space on virtual
24 machine filesystems. Unlike other tools, it doesn't just display the
25 amount of space allocated to a virtual machine, but can look inside
26 the virtual machine to see how much space is really being used.
28 It is like the L<df(1)> command, but for virtual machines, except that
29 it also works for Windows virtual machines.
31 If used without any arguments, C<virt-df> checks with libvirt to get a
32 list of all active and inactive guests, and performs a C<df>-type
33 operation on each one in turn, printing out the results.
35 If used with any argument(s), C<virt-df> performs a C<df>-type
36 operation on either the single named libvirt domain, or on the disk
37 image(s) listed on the command line (which must all belong to a single
38 VM). In this mode (with arguments), C<virt-df> will I<only work for a
39 single guest>. If you want to run on multiple guests, then you have
40 to invoke C<virt-df> multiple times.
42 Use the C<--csv> option to get a format which can be easily parsed by
43 other programs. Other options are mostly similar to standard C<df>
44 options. See below for the complete list.
58 Add I<file> which should be a disk image from a virtual machine. If
59 the virtual machine has multiple block devices, you must supply all of
60 them with separate I<-a> options.
62 The format of the disk image is auto-detected. To override this and
63 force a particular format use the I<--format=..> option.
67 =item B<--connect> URI
69 If using libvirt, connect to the given I<URI>. If omitted, then we
70 connect to the default libvirt hypervisor.
72 If you specify guest block devices directly (I<-a>), then libvirt is
77 Write out the results in CSV format (comma-separated values). This
78 format can be imported easily into databases and spreadsheets, but
79 read L</NOTE ABOUT CSV FORMAT> below.
83 =item B<--domain> guest
85 Add all the disks from the named libvirt guest.
87 =item B<--format=raw|qcow2|..>
91 The default for the I<-a> option is to auto-detect the format of the
92 disk image. Using this forces the disk format for I<-a> options which
93 follow on the command line. Using I<--format> with no argument
94 switches back to auto-detection for subsequent I<-a> options.
98 virt-df --format=raw -a disk.img
100 forces raw format (no auto-detection) for C<disk.img>.
102 virt-df --format=raw -a disk.img --format -a another.img
104 forces raw format (no auto-detection) for C<disk.img> and reverts to
105 auto-detection for C<another.img>.
107 If you have untrusted raw-format guest disk images, you should use
108 this option to specify the disk format. This avoids a possible
109 security problem with malicious guests (CVE-2010-3851).
113 =item B<--human-readable>
115 Print sizes in human-readable format.
117 You are not allowed to use I<-h> and I<--csv> at the same time.
119 =item B<--inodes> | B<-i>
121 Print inodes instead of blocks.
123 =item B<--one-per-guest>
125 Run one libguestfs appliance per guest. Normally C<virt-df> will
126 add the disks from several guests to a single libguestfs appliance.
128 You might use this option in the following circumstances:
134 If you think an untrusted guest might actively try to exploit the
135 libguestfs appliance kernel, then this prevents one guest from
136 interfering with the stats printed for another guest.
140 If the kernel has a bug which stops it from accessing a
141 filesystem in one guest (see for example RHBZ#635373) then
142 this allows libguestfs to continue and report stats for further
149 Print UUIDs instead of names. This is useful for following
150 a guest even when the guest is migrated or renamed, or when
151 two guests happen to have the same name.
153 Note that only domains that we fetch from libvirt come with UUIDs.
154 For disk images, we still print the disk image name even when
155 this option is specified.
161 Enable verbose messages for debugging.
167 Display version number and exit.
171 Enable tracing of libguestfs API calls.
175 =head1 NOTE ABOUT CSV FORMAT
177 Comma-separated values (CSV) is a deceptive format. It I<seems> like
178 it should be easy to parse, but it is definitely not easy to parse.
180 Myth: Just split fields at commas. Reality: This does I<not> work
181 reliably. This example has two columns:
185 Myth: Read the file one line at a time. Reality: This does I<not>
186 work reliably. This example has one row:
191 For shell scripts, use C<csvtool> (L<http://merjis.com/developers/csv>
192 also packaged in major Linux distributions).
194 For other languages, use a CSV processing library (eg. C<Text::CSV>
195 for Perl or Python's built-in csv library).
197 Most spreadsheets and databases can import CSV directly.
201 Libvirt guest names can contain arbitrary characters, some of which
202 have meaning to the shell such as C<#> and space. You may need to
203 quote or escape these characters on the command line. See the shell
204 manual page L<sh(1)> for details.
210 L<virt-filesystems(1)>,
212 L<http://libguestfs.org/>.
216 Richard W.M. Jones L<http://people.redhat.com/~rjones/>
220 Copyright (C) 2009-2010 Red Hat Inc.
222 This program is free software; you can redistribute it and/or modify
223 it under the terms of the GNU General Public License as published by
224 the Free Software Foundation; either version 2 of the License, or
225 (at your option) any later version.
227 This program is distributed in the hope that it will be useful,
228 but WITHOUT ANY WARRANTY; without even the implied warranty of
229 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
230 GNU General Public License for more details.
232 You should have received a copy of the GNU General Public License
233 along with this program; if not, write to the Free Software
234 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.