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VIRT-XML(1)		    Virtual Machine Manager		   VIRT-XML(1)

       virt-xml - Edit libvirt XML using command line options.


       virt-xml is a command line tool for editing libvirt XML using explicit
       command line options. See the EXAMPLES section at the end of this
       document to jump right in.

       Each virt-xml invocation requires 3 things: name of an existing domain
       to alter (or XML passed on stdin), an action to on the XML, and an XML
       change to make. actions are one of:

       --add-device: Append a new device definition to the XML
       --remove-device: Remove an existing device definition --edit: Edit an
       existing XML block --build-xml: Just build the requested XML block and
       print it (no domain or input XML are required here).

       An XML change is one instance of any of the XML options provided by
       virt-xml, for example --disk or --boot.

       virt-xml only allows one action and XML pair per invocation. If you
       need to make multiple edits, invoke the command multiple times.

       -c URI
	   Connect to a non-default hypervisor. See virt-install(1) for

	   domain is the name, UUID, or ID of the existing VM. This can be
	   omitted if using --build-xml, or if XML is passed on stdin.

	   When a domain is specified, the default output action is --define,
	   even if the VM is running. To update the running VM configuration,
	   add the --update option (but not all options/devices support
	   updating the running VM configuration).

	   If XML is passed on stdin, the default output is --print-xml.

       --edit [EDIT-OPTIONS]
	   Edit the specified XML block. EDIT-OPTIONS tell virt-xml which
	   block to edit. The type of XML that we are editing is decided by
	   XML option that is passed to virt-xml. So if --disk is passed,
	   EDIT-OPTIONS select which <disk> block to edit.

	   Certain XML options only ever map to a single XML block, like
	   --cpu, --security, --boot, --clock, and a few others. In those
	   cases, virt-xml will not complain if a corresponding XML block does
	   not already exist, it will create it for you.

	   Most XML options support a special value 'clearxml=yes'. When
	   combined with --edit, it will completely blank out the XML block
	   being edited before applying the requested changes. This allows
	   completely rebuilding an XML block. See EXAMPLES for some usage.

	   EDIT-OPTIONS examples:

	       --edit without any options implies 'edit the first block'. So
	       '--edit --disk DISK-OPTIONS' means 'edit the first <disk>'.

	       For the single XML block options mentioned above, plain
	       '--edit' without any options is what you always want to use.

	   --edit #
	       Select the specified XML block number. So '--edit 2 --disk
	       DISK-OPTS' means 'edit the second <disk>'. This option only
	       really applies for device XML.

	   --edit all
	       Modify every XML block of the XML option type. So '--edit all
	       --disk DISK-OPTS' means 'edit ever <disk> block'. This option
	       only really applies for device XML.

	       Modify every XML block that matches the passed device options.
	       The device options are in the same format as would be passed to
	       the XML option.

	       So '--edit path=/tmp/foo --disk DISK-OPTS' means 'edit every
	       <disk> with path /tmp/foo'. This option only really applies for
	       device XML.

	   Append the specified XML options to the XML <devices> list.
	   Example: '--add-device --disk DISK-OPTIONS' will create a new
	   <disk> block and add it to the XML.

	   This option will error if specified with a non-device XML option
	   (see --edit section for a partial list).

	   Remove the specified device from the XML. The device to remove is
	   chosen by the XML option, which takes arguments in the same format
	   as --edit. Examples

	   --remove-device --disk 2
	       Remove the second disk device

	   --remove-device --network all
	       Remove all network devices

	   --remove-device --sound pcspk
	       Remove all sound devices with model='pcspk'

	   This option will error if specified with a non-device XML option
	   (see --edit section for a partial list).

	   Just build the specified XML, and print it to stdout. No input
	   domain or input XML is required. Example: '--build-xml --disk
	   DISK-OPTIONS' will just print the new <disk> device.

	   This option will error if specified with an XML option that does
	   not map cleanly to a specific XML block, like --vcpus or --memory.

       These options decide what action to take after altering the XML. In the
       common case these do not need to be specified, as 'XML actions' will
       imply a default output action, described in detail above. These are
       only needed if you want to modify the default output.

	   If the specified domain is running, attempt to alter the running VM
	   configuration. If combined with --edit, this is an update
	   operation. If combined with --add-device, this is a device hotplug.
	   If combined with --remove-device, this is a device hotunplug.

	   Keep in mind, most XML properties and devices do not support live
	   update operations, so don't expect it to succeed in all cases.

	   Define the requested XML change. This is typically the default if
	   no output option is specified, but if a --print option is
	   specified, --define is required to force the change.

	   Print the generated XML change in unified diff format. If only this
	   output option is specified, all other output options are disabled
	   and no persistent change is made.

	   Print the generated XML in its entirety. If only this output option
	   is specified, all other output options are disabled and no
	   persistent change is made.

	   Before defining or updating the domain, show the generated XML diff
	   and interactively request confirmation.

	   These options alter the XML for a single class of XML elements.
	   More complete documentation is found in virt-install(1).

	   Generally these options map pretty straightforwardly to the libvirt
	   XML, documented at <http://libvirt.org/formatdomain.html>

	   Option strings are in the format of: --option opt=val,opt2=val2,...
	   example: --disk path=/tmp/foo,shareable=on. Properties can be used
	   with '--option opt=,', so to clear a disks cache setting you could
	   use '--disk cache=,'

	   For any option, use --option=? to see a list of all available sub
	   options, example: --disk=?  or  --boot=?

	   --help output also lists a few general examples. See the EXAMPLES
	   section below for some common examples.

	   Show the help message and exit

	   Show program's version number and exit

	   Avoid verbose output.

	   Print debugging information

       See a list of all suboptions that --disk and --network take

	 # virt-xml --disk=? --network=?

       Change the <description> of domain 'EXAMPLE':

	 # virt-xml EXAMPLE --edit --metadata description="my new description"

       # Enable the boot device menu for domain 'EXAMPLE':

	 # virt-xml EXAMPLE --edit --boot menu=on

       Clear the previous <cpu> definition of domain 'winxp', change it to
       'host-model', but interactively confirm the diff before saving:

	 # virt-xml winxp --edit --cpu host-model,clearxml=yes --confirm

       Change the second sound card to model=ich6 on 'fedora19', but only
       output the diff:

	 # virt-xml fedora19 --edit 2 --sound model=ich6 --print-diff

       Update the every graphics device password to 'foo' of the running VM

	 # virt-xml rhel6 --edit all --graphics password=foo --update

       Remove the disk path from disk device hdc:

	 # virt-xml rhel6 --edit target=hdc --disk path=

       Change all disk devices of type 'disk' to use cache=none, using XML
       from stdin, printing the new XML to stdout.

	 # cat <xmlfile> | virt-xml --edit device=disk --disk cache=none

       Change disk 'hda' IO to native and use startup policy as 'optional'.

	 # virt-xml fedora20 --edit target=hda \
		    --disk io=native,startup_policy=optional

       Change all host devices to use driver_name=vfio for VM 'fedora20' on
       the remote connection

	 # virt-xml --connect qemu+ssh://remotehost/system \
		    fedora20 --edit all --hostdev driver_name=vfio

       Hotplug host USB device 001.003 to running domain 'fedora19':

	 # virt-xml fedora19 --update --add-device --hostdev 001.003

       Add a spicevmc channel to the domain 'winxp', that will be available
       after the next VM shutdown.

	 # virt-xml winxp --add-device --channel spicevmc

       Create a 10G qcow2 disk image and attach it to 'fedora18' for the next
       VM startup:

	 # virt-xml fedora18 --add-device \
	   --disk /var/lib/libvirt/images/newimage.qcow2,format=qcow2,size=10

       Hotunplug the disk vdb from the running domain 'rhel7':

	 # virt-xml rhel7 --update --remove-device --disk target=vdb

       Remove all graphics devices from the VM 'rhel7' after the next

	 # virt-xml rhel7 --remove-device --graphics all

       Generate XML for a virtio console device and print it to stdout:

	 # virt-xml --build-xml --console pty,target_type=virtio

       Please see http://virt-manager.org/page/BugReporting

       Copyright (C) Red Hat, Inc, and various contributors.  This is free
       software. You may redistribute copies of it under the terms of the GNU
       General Public License "http://www.gnu.org/licenses/gpl.html".  There
       is NO WARRANTY, to the extent permitted by law.

       virt-install(1), the project website "http://virt-manager.org"

1.3.2				  2017-08-31			   VIRT-XML(1)