=encoding utf8 =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 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 where C is the libvirt domain (see: C). You can also run virt-inspector directly on disk images from a single virtual machine. Use C. 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 C, the second to the guest's C 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. 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). The same information can also be fetched using guestfish or via libguestfs bindings in many programming languages (see L). =head1 OPTIONS =over 4 =item B<--help> Display brief help. =item B<-a> file =item B<--add> file Add I 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<-c URI> =item B<--connect URI> If using libvirt, connect to the given I. If omitted, then we connect to the default libvirt hypervisor. Libvirt is only used if you specify a C 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 C. =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 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 C which is supplied with libguestfs. This section is just an overview. The top-level element is EoperatingsystemsE, and it contains one or more EoperatingsystemE elements. You would only see more than one EoperatingsystemE element if the virtual machine is multi-boot, which is vanishingly rare in real world VMs. =head2 EoperatingsystemE In the EoperatingsystemE 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: /dev/sda2 windows i386 windows Windows 7 Enterprise Client 6 1 /Windows installed In brief, EnameE is the class of operating system (something like C or C), EdistroE is the distribution (eg. C but many other distros are recognized) and EarchE 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. The ErootE 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 EmountpointsE Un*x-like guests typically have multiple filesystems which are mounted at various mountpoints, and these are described in the EmountpointsE element which looks like this: ... / /boot As with ErootE, 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 EfilesystemsE EfilesystemsE is like EmountpointsE but covers I 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: ... ext4 e6a4db1e-15c2-477b-ac2a-699181c396aa The optional elements within EfilesystemE are the filesystem type, the label, and the UUID. =head2 EapplicationsE The related elements Epackage_formatE, Epackage_managementE and EapplicationsE describe applications installed in the virtual machine. Epackage_formatE, if present, describes the packaging system used. Typical values would be C and C. Epackage_managementE, if present, describes the package manager. Typical values include C, C and C EapplicationsE lists the packages or applications installed. ... coreutils 8.5 1 The version and release fields may not be available for some types guests. Other fields are possible, see L. =head2 Edrive_mappingsE For operating systems like Windows which use drive letters, virt-inspector is able to find out how drive letters map to filesystems. ... /dev/sda2 /dev/sdb1 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 EiconE 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. ... iVBORw0KGgoAAAANSUhEUgAAAGAAAABg[.......] [... many lines of base64 data ...] 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 program to do the conversion back to a PNG file: base64 -i -d < icon.data > icon.png =head2 INSPECTING INSTALL DISKS, LIVE CDs Virt-inspector can detect some operating system installers on install disks, live CDs, bootable USB keys and more. In this case the EformatE tag will contain C and other fields may be present to indicate a live CD, network installer, or one part of a multipart CD. For example: /dev/sda linux i386 ubuntu Ubuntu 10.10 "Maverick Meerkat" 10 10 installer =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 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' ext4 [...] $ 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 SHELL QUOTING Libvirt guest names can contain arbitrary characters, some of which have meaning to the shell such as C<#> and space. You may need to quote or escape these characters on the command line. See the shell manual page L for details. =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). 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. For example code using the C inspection API, look for C which ships with libguestfs. C has also been translated into other languages. For example, C is the Perl translation, and there are other translations for OCaml, Python, etc. See L 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 is called. This is equivalent to the guestfish command C. You can also call this guestfish command by hand. C 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 > run > inspect-os /dev/vg_f15x32/lv_root Using the root device, you can fetch further information about the guest: > inspect-get-type /dev/vg_f15x32/lv_root linux > inspect-get-distro /dev/vg_f15x32/lv_root fedora > inspect-get-major-version /dev/vg_f15x32/lv_root 15 > 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: > inspect-get-mountpoints /dev/vg_f15x32/lv_root /: /dev/vg_f15x32/lv_root /boot: /dev/vda1 > mount-ro /dev/vg_f15x32/lv_root / > mount-ro /dev/vda1 /boot and then call the inspect-list-applications API: > 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: > 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, L, L, L, L, L. =head1 AUTHORS =over 4 =item * Richard W.M. Jones L =item * Matthew Booth L =back =head1 COPYRIGHT Copyright (C) 2010-2012 Red Hat Inc.