virt-df(1) Virtualization Support virt-df(1)NAMEvirt-df - Display free space on virtual filesystems
SYNOPSIS
All guests:
virt-df [--options]
Single guest:
virt-df [--options] -d domname
virt-df [--options] -a disk.img [-a disk.img ...]
Old style:
virt-df [--options] domname
virt-df [--options] disk.img [disk.img ...]
DESCRIPTION
"virt-df" is a command line tool to display free space on virtual
machine filesystems. Unlike other tools, it doesn't just display the
size of disk allocated to a virtual machine, but can look inside disk
images to see how much space is really being used.
If used without any -a or -d arguments, "virt-df" checks with libvirt
to get a list of all active and inactive guests, and performs a
"df"-type operation on each one in turn, printing out the results.
If any -a or -d arguments are specified, "virt-df" performs a "df"-type
operation on either the single named libvirt domain, or on the disk
image(s) listed on the command line (which must all belong to a single
VM). In this mode (with arguments), "virt-df" will only work for a
single guest. If you want to run on multiple guests, then you have to
invoke "virt-df" multiple times.
Use the --csv option to get a format which can be easily parsed by
other programs. Other options are similar to the standard df(1)
command.
EXAMPLES
Show disk usage for a single libvirt guest called "F14x64". Make the
output human-readable:
# virt-df-d F14x64 -h
Filesystem Size Used Available Use%
F14x64:/dev/sda1 484M 66M 393M 14%
F14x64:/dev/vg_f13x64/lv_root 7.4G 3.4G 4.0G 46%
Show disk usage for a disk image file called "test.img":
$ virt-df-a test1.img
Filesystem 1K-blocks Used Available Use%
test1.img:/dev/sda1 99099 1551 92432 2%
If a single guest has multiple disks, use the -a option repeatedly. A
plus sign ("+") is displayed for each additional disk. Note: Do not do
this with unrelated guest disks.
$ virt-df-a Win7x32TwoDisks-a -a Win7x32TwoDisks-b
Filesystem 1K-blocks Used Available Use%
Win7x32TwoDisks-a+:/dev/sda1 102396 24712 77684 25%
Win7x32TwoDisks-a+:/dev/sda2 12478460 7403416 5075044 60%
Win7x32TwoDisks-a+:/dev/sdb1 521212 55728 465484 11%
OPTIONS--help
Display brief help.
-a file
--add file
Add file which should be a disk image from a virtual machine. If
the virtual machine has multiple block devices, you must supply all
of them with separate -a options.
The format of the disk image is auto-detected. To override this
and force a particular format use the --format=.. option.
-c URI
--connect URI
If using libvirt, connect to the given URI. If omitted, then we
connect to the default libvirt hypervisor.
If you specify guest block devices directly (-a), then libvirt is
not used at all.
--csv
Write out the results in CSV format (comma-separated values). This
format can be imported easily into databases and spreadsheets, but
read "NOTE ABOUT CSV FORMAT" below.
-d guest
--domain guest
Add all the disks from the named libvirt guest. Domain UUIDs can
be used instead of names.
--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-df --format=raw -a disk.img
forces raw format (no auto-detection) for "disk.img".
virt-df --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).
-h
--human-readable
Print sizes in human-readable format.
You are not allowed to use -h and --csv at the same time.
-i
--inodes
Print inodes instead of blocks.
--one-per-guest
Run one libguestfs appliance per guest. Normally "virt-df" will
add the disks from several guests to a single libguestfs appliance.
You might use this option in the following circumstances:
· If you think an untrusted guest might actively try to exploit
the libguestfs appliance kernel, then this prevents one guest
from interfering with the stats printed for another guest.
· If the kernel has a bug which stops it from accessing a
filesystem in one guest (see for example RHBZ#635373) then this
allows libguestfs to continue and report stats for further
guests.
--uuid
Print UUIDs instead of names. This is useful for following a guest
even when the guest is migrated or renamed, or when two guests
happen to have the same name.
Note that only domains that we fetch from libvirt come with UUIDs.
For disk images, we still print the disk image name even when this
option is specified.
-v
--verbose
Enable verbose messages for debugging.
-V
--version
Display version number and exit.
-x Enable tracing of libguestfs API calls.
STATVFS NUMBERS
"virt-df" (and df(1)) get information by issuing a statvfs(3) system
call. You can get the same information directly, either from the host
(using libguestfs) or inside the guest:
From the host
Run this command:
guestfish --ro -d GuestName -i statvfs /
(change "/" to see stats for other filesystems).
From inside the guest
Run this command:
python -c 'import os; s = os.statvfs ("/"); print s'
(change "/" to see stats for other filesystems).
NOTE ABOUT CSV FORMAT
Comma-separated values (CSV) is a deceptive format. It seems like it
should be easy to parse, but it is definitely not easy to parse.
Myth: Just split fields at commas. Reality: This does not work
reliably. This example has two columns:
"foo,bar",baz
Myth: Read the file one line at a time. Reality: This does not work
reliably. This example has one row:
"foo
bar",baz
For shell scripts, use "csvtool" (http://merjis.com/developers/csv also
packaged in major Linux distributions).
For other languages, use a CSV processing library (eg. "Text::CSV" for
Perl or Python's built-in csv library).
Most spreadsheets and databases can import CSV directly.
SHELL QUOTING
Libvirt guest names can contain arbitrary characters, some of which
have meaning to the shell such as "#" and space. You may need to quote
or escape these characters on the command line. See the shell manual
page sh(1) for details.
EXIT STATUS
This program returns 0 if successful, or non-zero if there was an
error.
SEE ALSOdf(1), guestfs(3), guestfish(1), virt-filesystems(1),
http://libguestfs.org/.
AUTHOR
Richard W.M. Jones http://people.redhat.com/~rjones/
COPYRIGHT
Copyright (C) 2009-2013 Red Hat Inc.
LICENSE
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.
BUGS
To get a list of bugs against libguestfs, use this link:
https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
To report a new bug against libguestfs, use this link:
https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
When reporting a bug, please supply:
· The version of libguestfs.
· Where you got libguestfs (eg. which Linux distro, compiled from
source, etc)
· Describe the bug accurately and give a way to reproduce it.
· Run libguestfs-test-tool(1) and paste the complete, unedited output
into the bug report.
libguestfs-1.20.4 2013-03-12 virt-df(1)
