libvirt/docs/manpages/libvirt-guests.rst

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==============
libvirt-guests
==============
-------------------------------------
suspend/resume running libvirt guests
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:Manual section: 8
:Manual group: Virtualization Support
.. contents::
SYNOPSIS
========
``libvirt-guests`` *COMMAND*
DESCRIPTION
===========
``libvirt-guests`` is a service that can be used to coordinate guest and host
lifecycle actions. By default, ``libvirt-guests`` will suspend running guests
when the host shuts down, and restore them to their pre-shutdown state when
the host reboots.
``libvirt-guests`` is typically under control of systemd. When
``libvirt-guests.service`` is enabled, systemd will call ``libvirt-guests``
with the ``start`` *COMMAND* when the host boots. Conversely, systemd will call
``libvirt-guests`` with the ``stop`` *COMMAND* when the host shuts down.
``libvirt-guests`` can be used directly. In addition to the ``start`` and
``stop`` *COMMAND*\s, it also supports ``status``, ``restart``, ``condrestart``,
``try-restart``, ``reload``, ``force-reload``, ``gueststatus``, and
``shutdown`` *COMMAND*\s.
FILES
=====
``libvirt-guests`` defines several variables to control service behavior.
The default value of these variables can be overridden in:
* ``@INITCONFDIR@/libvirt-guests``
The following variables are supported:
- URIS=default
URIs to check for running guests. Example:
``URIS='default xen:///system xen+tcp://host/system lxc:///system'``
- ON_BOOT=start
Action taken on host boot
* start
All guests which were running on shutdown are started on boot regardless
of their autostart settings
* ignore
``libvirt-guests`` won't start any guest on boot, however, guests marked
as autostart will still be automatically started by libvirtd
- START_DELAY=0
Number of seconds to wait between each guest start. Set to 0 to allow parallel
startup.
- ON_SHUTDOWN=suspend
Action taken on host shutdown
* suspend
All running guests are suspended using virsh managedsave
* shutdown
All running guests are asked to shutdown. Please be careful with this
settings since there is no way to distinguish between a guest which is
stuck or ignores shutdown requests and a guest which just needs a long
time to shutdown. When setting ON_SHUTDOWN=shutdown, you must also set
SHUTDOWN_TIMEOUT to a value suitable for your guests.
- PARALLEL_SHUTDOWN=0
Number of guests will be shutdown concurrently, taking effect when
"ON_SHUTDOWN" is set to "shutdown". If Set to 0, guests will be shutdown one
after another. Number of guests on shutdown at any time will not exceed number
set in this variable.
- SHUTDOWN_TIMEOUT=300
Number of seconds we're willing to wait for a guest to shut down. If parallel
shutdown is enabled, this timeout applies as a timeout for shutting down all
guests on a single URI defined in the variable URIS. If this is 0, then there
is no time out (use with caution, as guests might not respond to a shutdown
request). The default value is 300 seconds (5 minutes).
- BYPASS_CACHE=0
If non-zero, try to bypass the file system cache when saving and
restoring guests, even though this may give slower operation for
some file systems.
- SYNC_TIME=0
If non-zero, try to sync guest time on domain resume. Be aware, that
this requires guest agent with support for time synchronization
running in the guest. By default, this functionality is turned off.
Extend libvirt-guests to shutdown only persistent VMs At the moment, there is no configuration option for the libvirt-guests service that allows users to define that only persistent virtual machines should be shutdown on host shutdown. Currently, the service config allows to choose between two ON_SHUTDOWN actions that are executed on running virtual machines when the host goes down: shutdown, suspend. The ON_SHUTDOWN action should be orthogonal to the type of the virtual machine. However, the existing implementation, does not suspend transient virtual machines. This is the matrix of actions that is executed on virtual machines based on the configured ON_SHUTDOWN action and the type of a virtual machine. | persistent | transient shutdown | shutdown | shutdown (what we want to change) suspend | suspend | nothing Add config option PERSISTENT_ONLY to libvirt-guests config that allows users to define if the ON_SHUTDOWN action should be applied only on persistent virtual machines. PERSISTENT_ONLY can be set to true, false, default. The default option will implement the already existing logic. Case 1: PERSISTENT_ONLY=default | persistent | transient shutdown | shutdown | shutdown suspend | suspend | nothing Case 2: PERSISTENT_ONLY=true | persistent | transient shutdown | shutdown | nothing suspend | suspend | nothing Case 3: PERSISTENT_ONLY=false | persistent | transient shutdown | shutdown | shutdown suspend | suspend | suspend Signed-off-by: Benjamin Taubmann <benjamin.taubmann@nutanix.com> Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
2024-03-26 11:37:21 +00:00
- PERSISTENT_ONLY=default
Defines what type of guest virtual machine ON_SHUTDOWN action is applied to
* default
This implements the already existing default behavior.
If ON_SHUTDOWN action is shutdown, transient and persistent guest virtual
machines are asked to shutdown.
If ON_SHUTDOWN action is suspend, only persistent guest virtual machines
are asked to suspend.
* true
ON_SHUTDOWN action is executed only on persistent guest virtual machines.
Transient guest virtual machines are not affected.
* false
ON_SHUTDOWN action is executed on persistent and transient guest virtual
machines.
BUGS
====
Please report all bugs you discover. This should be done via either:
#. the mailing list
`https://libvirt.org/contact.html <https://libvirt.org/contact.html>`_
#. the bug tracker
`https://libvirt.org/bugs.html <https://libvirt.org/bugs.html>`_
Alternatively, you may report bugs to your software distributor / vendor.
AUTHORS
=======
Please refer to the AUTHORS file distributed with libvirt.
LICENSE
=======
``libvirt-guests`` is distributed under the terms of the GNU LGPL v2.1+.
This is free software; see the source for copying conditions. There
is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE
SEE ALSO
========
libvirtd(8), `https://libvirt.org/ <https://libvirt.org/>`_