After some debugging and discussion with systemd team it turns out we
are misusing the ordering in libvirt-guests.service. That happened
because we want to support both monolithic and modular daemon setups and
on top of that we also want to support socket activation and services
without socket activation. Unfortunately this is impossible to express
in the unit file because of how transactions are handled in systemd when
dependencies are resolved and multiple actions (jobs) are queued. For
explanation from Michal Sekletar see comment #7 in the BZ this patch is
fixing:
https://bugzilla.redhat.com/show_bug.cgi?id=1964855#c7
In order to support all the scenarios this patch also amends the
manpages so that users that are changing the default can also read how
to correct the dependency ordering in libvirt-guests unit file.
Ideally we would also keep the existing configuration during upgrade,
but due to our huge support matrix this seems hardly feasible as it
could introduce even more problems.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since libvirt-guests script/service can operate on various URIs and we do
support both socket activation and traditional services, the ordering should be
specified for all the possible sockets and services.
Also remove the Wants= dependency since do not want to start any service. We
cannot know which one libvirt-guests is configured, so we'd have to start all
the daemons which would break if unused colliding services are not
masked (libvirtd.service in the modular case and all the modular daemon service
units in the monolithic scenario). Fortunately we can assume that the system is
configured properly to start services/sockets that are of interest to the user.
That also works with the setup described in https://libvirt.org/daemons.html .
To make it even more robust we add the daemon service into the machine units
created for individual domains as it was missing there.
https://bugzilla.redhat.com/show_bug.cgi?id=1868537
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Substitute in the @sysconfigdir@ value instead of /etc.
Reviewed-by: Christophe de Dinechin <dinechin@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
It is already discussed in "[RFC] daemon: remove hardcode dep on libvirt-guests" [1].
Mgmt can use means to save/restore domains on system shutdown/boot other than
libvirt-guests.service. Thus we need to specify appropriate ordering dependency between
libvirtd, domains and save/restore service. This patch takes approach suggested
in RFC and introduces a systemd target, so that ordering can be built next way:
libvirtd -> domain -> virt-guest-shutdown.target -> save-restore.service.
This way domains are decoupled from specific shutdown service via intermediate
target.
[1] https://www.redhat.com/archives/libvir-list/2016-September/msg01353.html
The Requires relationship is very strong, in that it prevents
a unit from running unless all the units it Requires are
running as well.
This turns out to be a problem because we want to be able to
restart libvirtd at any time without having libvirt-guests
suspend or shutdown running guests.
Turn the Requires relationship into a Wants relationship:
this way starting libvirt-guests will cause systemd to (attempt
to) start libvirtd as well, but stopping or restarting libvirtd
will not alter libvirt-guests' running state.
Having After=libvirtd.service merely ensures that, if both
services are asked to start, libvirtd.service will start
first.
What we really want is for libvirtd.service to be started
whenever libvirt-guests.service is asked to start. Adding a
Requires= relationship guarantees that will happen.
We use a separate line for each After= relationship in other
unit files: do the same here for consistency's sake, and also
to make future changes nicer to diff
libvirt-guests.service does both suspend *and* resume guests,
depending on whether it's being started or stopped: the
description should reflect this, to avoid confusing messages
during startup.
Replace "active" with "running" (to match virsh list's output)
and don't capitalize libvirt.
When libvirt-guests is configured to start guests on host
boot, it is possible for guests start and read the host
clock before it is synchronized. Services such as
libvirt-guests that require correct time should use the
Special Passive System Unit time-sync.target
http://www.freedesktop.org/software/systemd/man/systemd.special.html#time-sync.target
Most of this deals with moving the libvirt-guests.sh script which
does all the work to /usr/libexec, so it can be shared by both
systemd and traditional init. Previously systemd depended on
the script being in /etc/init.d
Required to fix https://bugzilla.redhat.com/show_bug.cgi?id=789747
Since the move to systemd libvirt-guests doesn't output this progress
information anymore. This patch brings back this feature.
It is helpful to show the admin what the system is waiting for and what
is left of the timeout (e.g. for calibrating the shutdown timing of a ups).
Rewriting the current line with \r doesn't work anymore in the context
of systemd. So always write new lines, but move to 5 second intervals
to avoid flooding the console.
I originally postet this into the Fedora bugzilla
https://bugzilla.redhat.com/show_bug.cgi?id=843836
Currently gracefully shutting down guest vms on host shutdown does not work on
Fedora 17, the guests are killed hard on system shutdown.
The reason is systemd considers libvirt-guests.service to be stopped when the
system is running:
$ systemctl status libvirt-guests.service
libvirt-guests.service - Suspend Active Libvirt Guests
Loaded: loaded (/usr/lib/systemd/system/libvirt-guests.service;
enabled)
Active: deactivating (stop) since Fri, 27 Jul 2012 15:47:31 +0200;
2min 48s ago
Process: 1085 ExecStart=/etc/init.d/libvirt-guests start
(code=exited, status=0/SUCCESS)
Control: 1150 (libvirt-guests)
CGroup: name=systemd:/system/libvirt-guests.service
└ control
├ 1150 /bin/sh /etc/init.d/libvirt-guests stop
└ 2257 sleep 1
libvirt-guests.service is defined as type "simple" in systemd (the default).
That means systemd will shut down the service when the start executable is
terminated after starting is done. Systemd will not call stop again on system
shutdown because it thinks it is already stopped.
The solution is to define it as type "oneshot" and set the flag
"RemainAfterExit". Then systemd will consider the service as active after
startup and will call the stop function on host shutdown.
This patch adds support for a systemd init service for libvirtd
and libvirt-guests. The libvirtd.service is *not* written to use
socket activation, since we want libvirtd to start on boot so it
can do guest auto-start.
The libvirt-guests.service is pretty lame, just exec'ing the
original init script for now. Ideally we would factor out the
functionality, into some shared tool.
Instead of
./configure --with-init-script=redhat
You can now do
./configure --with-init-script=systemd
Or better still:
./configure --with-init-script=systemd+redhat
We can also now support install of the upstart init script
* configure.ac: Add systemd, and systemd+redhat options to
--with-init-script option
* daemon/Makefile.am: Install systemd services
* daemon/libvirtd.sysconf: Add note about unused env variable
with systemd
* daemon/libvirtd.service.in: libvirtd systemd service unit
* libvirt.spec.in: Add scripts to installing systemd services
and migrating from legacy init scripts
* tools/Makefile.am: Install systemd services
* tools/libvirt-guests.init.sh: Rename to tools/libvirt-guests.init.in
* tools/libvirt-guests.service.in: systemd service unit
