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guestfs-recipes(1)					      Virtualization Support						guestfs-recipes(1)

NAME

       guestfs-recipes - libguestfs, guestfish and virt tools recipes

DESCRIPTION

       This page contains recipes for and links to things you can do using libguestfs, guestfish(1) and the virt tools.

Audit a virtual machine for setuid files
       The link below contains a small program which can be used to audit a Linux virtual machine to see what setuid and setgid files it contains.

       https://rwmj.wordpress.com/2010/12/15/tip-audit-virtual-machine-for-setuid-files/#content

Change the background image in a Windows XP VM
       The links below explain how to use guestfish(1) to change the background image for a user of a Windows XP VM.  Unfortunately the technique
       appears to be substantially different for each version of Windows.

       https://lists.fedoraproject.org/pipermail/virt/2011-May/002655.html https://lists.fedoraproject.org/pipermail/virt/2011-May/002658.html

Cloning a virtual machine (Linux)
       The guestfish technique described in the link below works well for most Linux VMs.  Depending on the Linux distro you may need to change
       the paths slightly.

       https://rwmj.wordpress.com/2010/09/24/tip-my-procedure-for-cloning-a-fedora-vm/#content

       Avoid virt-clone(1).  Currently what to do about virt-clone is under discussion.

       https://www.redhat.com/archives/virt-tools-list/2011-May/msg00019.html

Cloning a virtual machine (Windows)
       It is possible to do a "sysprep" using libguestfs alone, although not straightforward.  Currently there is code in the Aeolus Oz project
       which does this (using libguestfs).  As part of our review of the virt-clone tool, we may add sysprepping ability.

       https://github.com/clalancette/oz https://www.redhat.com/archives/virt-tools-list/2011-May/msg00019.html

Convert a CD-ROM / DVD / ISO to a tarball
       This converts input "cd.iso" to output "cd.tar.gz":

	guestfish --ro -a cd.iso -m /dev/sda tgz-out / cd.tar.gz

       To export just a subdirectory, eg. "/files", do:

	guestfish --ro -a cd.iso -m /dev/sda tgz-out /files cd.tar.gz

Create empty disk images
       You can use the guestfish(1) -N option to create empty disk images.  The useful guide below explains the options available.

       https://rwmj.wordpress.com/2010/09/08/new-guestfish-n-options-in-1-5-9/#content

Dump raw filesystem content from inside a disk image or VM
       You can use the guestfish(1) "download" command to extract the raw filesystem content from any filesystem in a disk image or a VM (even one
       which is encrypted or buried inside an LV):

	guestfish --ro -a disk.img run : download /dev/sda1 sda1.img

	guestfish --ro -d Guest run : download /dev/vg_guest/lv_root lv.img

       To list the filesystems in a disk image, use virt-filesystems(1).

Edit grub configuration in a VM
       You can use this to:

       o   Fix a virtual machine that does not boot.

       o   Change which kernel is used to boot the VM.

       o   Change kernel command line options.

       Use virt-edit(1) to edit the grub configuration:

	virt-edit -d BrokenGuest /boot/grub/grub.conf

       or for general tinkering inside an unbootable VM use virt-rescue(1) like this:

	virt-rescue -d BrokenGuest

Export any directory from a VM
       To export "/home" from a VM into a local directory use virt-copy-out(1):

	virt-copy-out -d Guest /home .

       Notes:

       o   The final dot of the command is not a printing error.  It means we want to copy out to the current directory.

       o   This creates a directory called "home" under the current directory.

       If the guest is a Windows guest then you can use drive letters and backslashes, but you must prefix the path with "win:" and quote it to
       protect it from the shell, like this:

	virt-copy-out -d WinGuest 'win:c:windowssystem32config' .

       To get the output as a compressed tarball, do:

	virt-tar-out -d Guest /home - | gzip --best > home.tar.gz

       Although it sounds tempting, this is usually not a reliable way to get a backup from a running guest.  See the entry in the FAQ:
       http://libguestfs.org/FAQ.html#backup

Find out which user is using the most space
       This simple script examines a Linux guest to find out which user is using the most space in their home directory:

	#!/bin/sh -

	set -e

	vm="$1"
	dir=/home

	eval $(guestfish --ro -d "$vm" -i --listen)

	for d in $(guestfish --remote ls "$dir"); do
	    echo -n "$dir/$d"
	    echo -ne '	'
	    guestfish --remote du "$dir/$d";
	done | sort -nr -k 2

	guestfish --remote exit

Get DHCP address from a VM
       The link below explains the many different possible techniques for getting the last assigned DHCP address of a virtual machine.

       https://rwmj.wordpress.com/2011/03/31/tip-code-for-getting-dhcp-address-from-a-virtual-machine-disk-image/#content

       In the libguestfs source examples directory you will find the latest version of the "virt-dhcp-address.c" program.

Get the operating system product name string
       Save the following script into a file called "product-name.sh":

	#!/bin/sh -
	set -e
	eval "$(guestfish --ro -d "$1" --i --listen)"
	root="$(guestfish --remote inspect-get-roots)"
	guestfish --remote inspect-get-product-name "$root"
	guestfish --remote exit

       Make the script executable and run it on a named guest:

	# product-name.sh RHEL60x64
	Red Hat Enterprise Linux Server release 6.0 (Santiago)

       You can also use an XPath query on the virt-inspector(1) XML using the "xpath" command line tool or from your favourite programming
       language:

	# virt-inspector RHEL60x64 > xml
	# xpath '//product_name' < xml
	Found 1 nodes:
	-- NODE --
	<product_name>Red Hat Enterprise Linux Server release 6.0 (Santiago)</product_name>

Get the default boot kernel for a Linux VM
       The link below contains a program to print the default boot kernel for a Linux VM.

       https://rwmj.wordpress.com/2010/10/30/tip-use-augeas-to-get-the-default-boot-kernel-for-a-vm/#content

       It uses Augeas, and the technique is generally applicable for many different tasks, such as:

       o   listing the user accounts in the guest

       o   what repositories is it configured to use

       o   what NTP servers does it connect to

       o   what were the boot messages last time it booted

       o   listing who was logged in recently

       http://augeas.net/

Install RPMs in a guest
       The link below contains a method to install RPMs in a guest.  In fact the RPMs are just uploaded to the guest along with a "firstboot"
       script that installs them next time the guest is booted.  You could use this technique to install vital security updates in an offline
       guest.

       https://rwmj.wordpress.com/2010/12/01/tip-install-rpms-in-a-guest/#content

List applications installed in a VM
       Save the following to a file "list-apps.sh":

	#!/bin/sh -
	set -e
	eval "$(guestfish --ro -d "$1" --i --listen)"
	root="$(guestfish --remote inspect-get-roots)"
	guestfish --remote inspect-list-applications "$root"
	guestfish --remote exit

       Make the file executable and then you can run it on any named virtual machine:

	# list-apps.sh WinGuest
	[0] = {
	  app_name: Mozilla Firefox (3.6.12)
	  app_display_name: Mozilla Firefox (3.6.12)
	  app_epoch: 0
	  app_version: 3.6.12 (en-GB)
	  app_release:
	  app_install_path: C:Program FilesMozilla Firefox
	  app_trans_path:
	  app_publisher: Mozilla
	  app_url: http://www.mozilla.com/en-GB/
	  app_source_package:
	  app_summary:
	  app_description: Mozilla Firefox
	}
	[1] = {
	  app_name: VLC media player
	  app_display_name: VLC media player 1.1.5
	  app_epoch: 0
	  app_version: 1.1.5
	  app_release:
	  app_install_path: C:Program FilesVideoLANVLC
	  app_trans_path:
	  app_publisher: VideoLAN
	  app_url: http://www.videolan.org/
	  app_source_package:
	  app_summary:
	  app_description:
	}

       If you want to run the script on disk images (instead of libvirt virtual machines), change "-d "$1"" to "-a "$1"".  See also
       virt-inspector(1).

List files and directories in a VM
       This involves using the guestfish(1) "find0" command like this:

	guestfish --ro -d Guest -i find0 / - | tr '' '
' | sort

List services in a Windows VM
       The link below contains a script that can be used to list out the services from a Windows VM, and whether those services run at boot time
       or are loaded on demand.

       https://rwmj.wordpress.com/2010/12/10/tip-list-services-in-a-windows-guest/#content

Make a disk image sparse
       The link below contains some guides for making a disk image sparse (or reintroducing sparseness).

       https://rwmj.wordpress.com/2010/10/19/tip-making-a-disk-image-sparse/#content

Monitor disk usage over time
       You can use virt-df(1) to monitor disk usage of your guests over time.  The link below contains a guide.

       http://virt-tools.org/learning/advanced-virt-df/

Reading the Windows Event Log from Windows Vista (or later)
       guestfish(1) plus the tools described in the link below can be used to read out the Windows Event Log from any virtual machine running
       Windows Vista or a later version.

       https://rwmj.wordpress.com/2011/04/17/decoding-the-windows-event-log-using-guestfish/#content

Remove root password (Linux)
       Using the virt-edit(1) -e option you can do simple replacements on files.  One use is to remove the root password from a Linux guest:

	virt-edit domname /etc/passwd -e 's/^root:.*?:/root::/'

Remove Administrator password (Windows)
       The link below contains one technique for removing the Administrator password from a Windows VM, or to be more precise, it gives you a
       command prompt the next time you log in which you can use to bypass any security:

       https://mdbooth.wordpress.com/2010/10/18/resetting-a-windows-guests-administrator-password-with-guestfish/

Unpack a live CD
       Linux live CDs often contain multiple layers of disk images wrapped like a Russian doll.  You can use guestfish(1) to look inside these
       multiple layers, as outlined in the guide below.

       https://rwmj.wordpress.com/2009/07/15/unpack-the-russian-doll-of-a-f11-live-cd/#content

Uploading and downloading files
       The link below contains general tips on uploading (copying in) and downloading (copying out) files from VMs.

       https://rwmj.wordpress.com/2010/12/02/tip-uploading-and-downloading/#content

Use libguestfs tools on VMware ESX guests
       The link below explains how to use libguestfs, guestfish(1) and the virt tools on any VMware ESX guests, by first sharing the VMware VMFS
       over sshfs.

       https://rwmj.wordpress.com/2011/05/10/tip-use-libguestfs-on-vmware-esx-guests/#content

SEE ALSO

       guestfs(3), guestfish(1), guestfs-examples(3), guestfs-erlang(3), guestfs-java(3), guestfs-ocaml(3), guestfs-perl(3), guestfs-python(3),
       guestfs-ruby(3), <http://libguestfs.org/>.

AUTHORS

       Richard W.M. Jones ("rjones at redhat dot com")

COPYRIGHT

       Copyright (C) 2009-2012 Red Hat Inc. <http://libguestfs.org/>

       The examples in this manual page may be freely copied, modified and distributed without any restrictions.

       This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as
       published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

       This library 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 Lesser General Public License for more details.

       You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software
       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

libguestfs-1.18.1						    2013-12-07							guestfs-recipes(1)