=head1 NAME

virt-inspector - Display operating system version and other information about a virtual machine

=head1 SYNOPSIS

 virt-inspector [--options] -d domname

 virt-inspector [--options] -a disk.img [-a disk.img ...]

Old-style:

 virt-inspector domname

 virt-inspector disk.img [disk.img ...]

=head1 DESCRIPTION

B<virt-inspector> examines a virtual machine or disk image and tries
to determine the version of the operating system and other information
about the virtual machine.

Virt-inspector produces XML output for feeding into other programs.

In the normal usage, use C<virt-inspector -d domname> where C<domname> is
the libvirt domain (see: C<virsh list --all>).

You can also run virt-inspector directly on disk images from a single
virtual machine.  Use C<virt-inspector -a disk.img>.  In rare cases a
domain has several block devices, in which case you should list
several I<-a> options one after another, with the first corresponding
to the guest’s F</dev/sda>, the second to the guest’s F</dev/sdb> and
so on.

You can also run virt-inspector on install disks, live CDs, bootable
USB keys and similar.

Virt-inspector can only inspect and report upon I<one domain at a
time>.  To inspect several virtual machines, you have to run
virt-inspector several times (for example, from a shell script
for-loop).

Because virt-inspector needs direct access to guest images, it won’t
normally work over remote libvirt connections.

All of the information available from virt-inspector is also available
through the core libguestfs inspection API (see
L<guestfs(3)/INSPECTION>).  The same information can also be fetched
using guestfish or via libguestfs bindings in many programming
languages (see L</GETTING INSPECTION DATA FROM THE LIBGUESTFS API>).

=head1 OPTIONS

=over 4

=item B<--help>

Display brief help.

=item B<-a> file

=item B<--add> file

Add I<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 I<-a> options.

The format of the disk image is auto-detected.  To override this and
force a particular format use the I<--format=..> option.

=item B<-a> URI

=item B<--add> URI

Add a remote disk.  See L<guestfish(1)/ADDING REMOTE STORAGE>.

=item B<-c> URI

=item B<--connect> URI

If using libvirt, connect to the given I<URI>.  If omitted,
then we connect to the default libvirt hypervisor.

Libvirt is only used if you specify a C<domname> on the
command line.  If you specify guest block devices directly (I<-a>),
then libvirt is not used at all.

=item B<-d> guest

=item B<--domain> guest

Add all the disks from the named libvirt guest.  Domain UUIDs can be
used instead of names.

=item B<--echo-keys>

When prompting for keys and passphrases, virt-inspector normally turns
echoing off so you cannot see what you are typing.  If you are not
worried about Tempest attacks and there is no one else in the room you
can specify this flag to see what you are typing.

=item B<--format=raw|qcow2|..>

=item B<--format>

Specify the format of disk images given on the command line.  If this
is omitted then the format is autodetected from the content of the
disk image.

If disk images are requested from libvirt, then this program asks
libvirt for this information.  In this case, the value of the format
parameter is ignored.

If working with untrusted raw-format guest disk images, you should
ensure the format is always specified.

=item B<--keys-from-stdin>

Read key or passphrase parameters from stdin.  The default is
to try to read passphrases from the user by opening F</dev/tty>.

=item B<--no-applications>

By default the output of virt-inspector includes the list of all the
applications installed in the guest, if available.

Specify this option to disable this part of the resulting XML.

=item B<--no-icon>

By default the output of virt-inspector includes the icon of the
guest, if available (see L</icon>).

Specify this option to disable this part of the resulting XML.

=item B<-v>

=item B<--verbose>

Enable verbose messages for debugging.

=item B<-V>

=item B<--version>

Display version number and exit.

=item B<-x>

Enable tracing of libguestfs API calls.

=item B<--xpath> query

Perform an XPath query on the XML on stdin, and print the result on
stdout.  In this mode virt-inspector simply runs an XPath query; all
other inspection functions are disabled.  See L</XPATH QUERIES> below
for some examples.

=back

=head1 OLD-STYLE COMMAND LINE ARGUMENTS

Previous versions of virt-inspector allowed you to write either:

 virt-inspector disk.img [disk.img ...]

or

 virt-inspector guestname

whereas in this version you should use I<-a> or I<-d> respectively
to avoid the confusing case where a disk image might have the same
name as a guest.

For compatibility the old style is still supported.

=head1 XML FORMAT

The virt-inspector XML is described precisely in a RELAX NG schema
file F<virt-inspector.rng> which is supplied with libguestfs.  This
section is just an overview.

The top-level element is E<lt>operatingsystemsE<gt>, and it contains
one or more E<lt>operatingsystemE<gt> elements.  You would only see
more than one E<lt>operatingsystemE<gt> element if the virtual machine
is multi-boot, which is vanishingly rare in real world VMs.

=head2 E<lt>operatingsystemE<gt>

In the E<lt>operatingsystemE<gt> tag are various optional fields that
describe the operating system, its architecture, the descriptive
"product name" string, the type of OS and so on, as in this example:

 <operatingsystems>
   <operatingsystem>
     <root>/dev/sda2</root>
     <name>windows</name>
     <arch>i386</arch>
     <distro>windows</distro>
     <product_name>Windows 7 Enterprise</product_name>
     <product_variant>Client</product_variant>
     <major_version>6</major_version>
     <minor_version>1</minor_version>
     <windows_systemroot>/Windows</windows_systemroot>

In brief, E<lt>nameE<gt> is the class of operating system (something
like C<linux> or C<windows>), E<lt>distroE<gt> is the distribution
(eg. C<fedora> but many other distros are recognized) and
E<lt>archE<gt> is the guest architecture.  The other fields are fairly
self-explanatory, but because these fields are taken directly from the
libguestfs inspection API you can find precise information from
L<guestfs(3)/INSPECTION>.

The E<lt>rootE<gt> element is the root filesystem device, but from the
point of view of libguestfs (block devices may have completely
different names inside the VM itself).

=head2 E<lt>mountpointsE<gt>

Un*x-like guests typically have multiple filesystems which are mounted
at various mountpoints, and these are described in the
E<lt>mountpointsE<gt> element which looks like this:

 <operatingsystems>
   <operatingsystem>
     ...
     <mountpoints>
       <mountpoint dev="/dev/vg_f13x64/lv_root">/</mountpoint>
       <mountpoint dev="/dev/sda1">/boot</mountpoint>
     </mountpoints>

As with E<lt>rootE<gt>, devices are from the point of view of
libguestfs, and may have completely different names inside the guest.
Only mountable filesystems appear in this list, not things like swap
devices.

=head2 E<lt>filesystemsE<gt>

E<lt>filesystemsE<gt> is like E<lt>mountpointsE<gt> but covers I<all>
filesystems belonging to the guest, including swap and empty
partitions.  (In the rare case of a multi-boot guest, it covers
filesystems belonging to this OS or shared with this OS and other
OSes).

You might see something like this:

 <operatingsystems>
   <operatingsystem>
     ...
     <filesystems>
       <filesystem dev="/dev/vg_f13x64/lv_root">
         <type>ext4</type>
         <label>Fedora-13-x86_64</label>
         <uuid>e6a4db1e-15c2-477b-ac2a-699181c396aa</uuid>
       </filesystem>

The optional elements within E<lt>filesystemE<gt> are the filesystem
type, the label, and the UUID.

=head2 E<lt>applicationsE<gt>

The related elements E<lt>package_formatE<gt>,
E<lt>package_managementE<gt> and E<lt>applicationsE<gt> describe
applications installed in the virtual machine.

E<lt>package_formatE<gt>, if present, describes the packaging
system used.  Typical values would be C<rpm> and C<deb>.

E<lt>package_managementE<gt>, if present, describes the package
manager.  Typical values include C<yum>, C<up2date> and C<apt>

E<lt>applicationsE<gt> lists the packages or applications
installed.

 <operatingsystems>
   <operatingsystem>
     ...
     <applications>
       <application>
         <name>coreutils</name>
         <version>8.5</version>
         <release>1</release>
       </application>

The version and release fields may not be available for some types
guests.  Other fields are possible, see
L<guestfs(3)/guestfs_inspect_list_applications>.

=head2 E<lt>drive_mappingsE<gt>

For operating systems like Windows which use drive letters,
virt-inspector is able to find out how drive letters map to
filesystems.

 <operatingsystems>
   <operatingsystem>
     ...
     <drive_mappings>
       <drive_mapping name="C">/dev/sda2</drive_mapping>
       <drive_mapping name="E">/dev/sdb1</drive_mapping>
     </drive_mappings>

In the example above, drive C maps to the filesystem on the second
partition on the first disk, and drive E maps to the filesystem on the
first partition on the second disk.

Note that this only covers permanent local filesystem mappings, not
things like network shares.  Furthermore NTFS volume mount points may
not be listed here.

=head2 E<lt>iconE<gt>

Virt-inspector is sometimes able to extract an icon or logo for the
guest.  The icon is returned as base64-encoded PNG data.  Note that
the icon can be very large and high quality.

 <operatingsystems>
   <operatingsystem>
     ...
     <icon>
       iVBORw0KGgoAAAANSUhEUgAAAGAAAABg[.......]
       [... many lines of base64 data ...]
     </icon>

To display the icon, you have to extract it and convert the base64
data back to a binary file.  Use an XPath query or simply an editor to
extract the data, then use the coreutils L<base64(1)> program to do
the conversion back to a PNG file:

 base64 -i -d < icon.data > icon.png

=head1 XPATH QUERIES

Virt-inspector includes built in support for running XPath queries.
The reason for including XPath support directly in virt-inspector is
simply that there are no good and widely available command line
programs that can do XPath queries.  The only good one is
L<xmlstarlet(1)> and that is not available on Red Hat Enterprise
Linux.

To perform an XPath query, use the I<--xpath> option.  Note that in
this mode, virt-inspector simply reads XML from stdin and outputs the
query result on stdout.  All other inspection features are disabled in
this mode.

For example:

 $ virt-inspector -d Guest | virt-inspector --xpath '//filesystems'
 <filesystems>
      <filesystem dev="/dev/vg_f13x64/lv_root">
        <type>ext4</type>
 [...]

 $ virt-inspector -d Guest | \
     virt-inspector --xpath "string(//filesystem[@dev='/dev/sda1']/type)"
 ext4

 $ virt-inspector -d Guest | \
     virt-inspector --xpath 'string(//icon)' | base64 -i -d | display -
 [displays the guest icon, if there is one]

=head1 GETTING INSPECTION DATA FROM THE LIBGUESTFS API

In early versions of libguestfs, virt-inspector was a large Perl
script that contained many heuristics for inspecting guests.  This had
several problems: in order to do inspection from other tools (like
guestfish) we had to call out to this Perl script; and it privileged
Perl over other languages that libguestfs supports.

By libguestfs 1.8 we had rewritten the Perl code in C, and
incorporated it all into the core libguestfs API (L<guestfs(3)>).  Now
virt-inspector is simply a thin C program over the core C API.  All of
the inspection information is available from all programming languages
that libguestfs supports, and from guestfish.

For a description of the C inspection API, read
L<guestfs(3)/INSPECTION>.

For example code using the C inspection API, look for F<inspect-vm.c>
which ships with libguestfs.

F<inspect-vm.c> has also been translated into other languages.  For
example, F<inspect_vm.pl> is the Perl translation, and there are other
translations for OCaml, Python, etc.  See
L<guestfs(3)/USING LIBGUESTFS WITH OTHER PROGRAMMING LANGUAGES> for a
list of man pages which contain this example code.

=head2 GETTING INSPECTION DATA FROM GUESTFISH

If you use the guestfish I<-i> option, then the main C inspection API
L<guestfs(3)/guestfs_inspect_os> is called.  This is equivalent to the
guestfish command C<inspect-os>.  You can also call this guestfish
command by hand.

C<inspect-os> performs inspection on the current disk image, returning
the list of operating systems found.  Each OS is represented by its
root filesystem device.  In the majority of cases, this command prints
nothing (no OSes found), or a single root device, but beware that it
can print multiple lines if there are multiple OSes or if there is an
install CD attached to the guest.

 $ guestfish --ro -a F15x32.img
 ><fs> run
 ><fs> inspect-os
 /dev/vg_f15x32/lv_root

Using the root device, you can fetch further information about the
guest:

 ><fs> inspect-get-type /dev/vg_f15x32/lv_root
 linux
 ><fs> inspect-get-distro /dev/vg_f15x32/lv_root
 fedora
 ><fs> inspect-get-major-version /dev/vg_f15x32/lv_root
 15
 ><fs> inspect-get-product-name /dev/vg_f15x32/lv_root
 Fedora release 15 (Lovelock)

Limitations of guestfish make it hard to assign the root device to a
variable (since guestfish doesn't have variables), so if you want to
do this reproducibly you are better off writing a script using one of
the other languages that the libguestfs API supports.

To list applications, you have to first mount up the disks:

 ><fs> inspect-get-mountpoints /dev/vg_f15x32/lv_root
 /: /dev/vg_f15x32/lv_root
 /boot: /dev/vda1
 ><fs> mount-ro /dev/vg_f15x32/lv_root /
 ><fs> mount-ro /dev/vda1 /boot

and then call the inspect-list-applications API:

 ><fs> inspect-list-applications /dev/vg_f15x32/lv_root | head -28
 [0] = {
   app_name: ConsoleKit
   app_display_name:
   app_epoch: 0
   app_version: 0.4.5
   app_release: 1.fc15
   app_install_path:
   app_trans_path:
   app_publisher:
   app_url:
   app_source_package:
   app_summary:
   app_description:
 }
 [1] = {
   app_name: ConsoleKit-libs
   app_display_name:
   app_epoch: 0
   app_version: 0.4.5
   app_release: 1.fc15
   app_install_path:
   app_trans_path:
   app_publisher:
   app_url:
   app_source_package:
   app_summary:
   app_description:
 }

To display an icon for the guest, note that filesystems must also be
mounted as above.  You can then do:

 ><fs> inspect-get-icon /dev/vg_f15x32/lv_root | display -

=head1 OLD VERSIONS OF VIRT-INSPECTOR

As described above, early versions of libguestfs shipped with a
different virt-inspector program written in Perl (the current version
is written in C).  The XML output of the Perl virt-inspector was
different and it could also output in other formats like text.

The old virt-inspector is no longer supported or shipped with
libguestfs.

To confuse matters further, in Red Hat Enterprise Linux 6 we ship two
versions of virt-inspector with different names:

 virt-inspector     Old Perl version.
 virt-inspector2    New C version.

=head1 EXIT STATUS

This program returns 0 if successful, or non-zero if there was an
error.

=head1 SEE ALSO

L<guestfs(3)>,
L<guestfish(1)>,
L<http://www.w3.org/TR/xpath/>,
L<base64(1)>,
L<xmlstarlet(1)>,
L<http://libguestfs.org/>.

=head1 AUTHORS

=over 4

=item *

Richard W.M. Jones L<http://people.redhat.com/~rjones/>

=item *

Matthew Booth L<mbooth@redhat.com>

=back

=head1 COPYRIGHT

Copyright (C) 2010-2012 Red Hat Inc.
