Refine waiting for vif plug events during _hard_reboot

In change Ib0cf5d55750f13d0499a570f14024dca551ed4d4, we stopped waiting
for vif plug events during hard reboot and start, because the behavior
of neutron plug events depended on the vif type and we couldn't rely on
the stale network info cache.

This refines the logic not to wait for vif plug events only for the
bridge vif type, instead of for all types. We also add a flag to
_create_domain_and_network to indicate that we're in the middle of a
reboot and to expect to wait for plug events for all vif types except
the bridge vif type, regardless of the vif's 'active' status.

We only query network_info from neutron at the beginning of a reboot,
before we've unplugged anything, so the majority of the time, the vifs
will be active=True. The current logic in get_neutron_events will only
expect events for vifs with 'active' status False. This adds a way to
override that if we know we've already unplugged vifs as part of a


NOTE(lyarwood): Ica323b87fa85a454fca9d46ada3677f18fe50022 and
I13de970c3beed29311d43991115a0c6d28ac14e0 are the source of the above
conflicts in The first removed encryptor attach logic from
_create_domain_and_network in Queens while the second altered the
signature of _create_domain_and_network in Queens, removing reboot that
is then reintroduced with this change.

Related-Bug: #1744361

Change-Id: Ib08afad3822f2ca95cfeea18d7f4fc4cb407b4d6
(cherry picked from commit aaf37a26d6)
(cherry picked from commit 5a10047f9d)
melanie witt 5 years ago committed by Lee Yarwood
parent b54aa791e2
commit e06ad602f3
  1. 37
  2. 64

@ -12087,6 +12087,28 @@ class LibvirtConnTestCase(test.NoDBTestCase,
instance, [], None)
def test_create_domain_and_network_reboot(self, mock_create, mock_handler,
mock_plug, mock_events):
# Verify that we call get_neutron_events with reboot=True if
# create_domain_and_network was called with reboot=True
drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
instance = objects.Instance(**self.test_instance)
network_info = _fake_network_info(self, 1)
@mock.patch.object(drvr.firewall_driver, 'setup_basic_filtering')
@mock.patch.object(drvr.firewall_driver, 'prepare_instance_filter')
@mock.patch.object(drvr.firewall_driver, 'apply_instance_filter')
def _do_create(mock_apply, mock_prepare, mock_setup):
drvr._create_domain_and_network(self.context, mock.sentinel.xml,
instance, network_info,
mock_events.assert_called_once_with(network_info, reboot=True)
@ -12149,7 +12171,7 @@ class LibvirtConnTestCase(test.NoDBTestCase,
dummyxml, instance, network_info,
block_device_info=block_device_info, vifs_already_plugged=True)
block_device_info=block_device_info, reboot=True)
@ -15042,6 +15064,19 @@ class LibvirtConnTestCase(test.NoDBTestCase,
events = drvr._get_neutron_events(network_info)
self.assertEqual([('network-vif-plugged', '1')], events)
def test_get_neutron_events_reboot(self):
drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
bridge = network_model.VIF_TYPE_BRIDGE
ovs = network_model.VIF_TYPE_OVS
network_info = [network_model.VIF(id='1'),
network_model.VIF(id='2', active=True),
network_model.VIF(id='3', type=bridge),
network_model.VIF(id='4', type=ovs)]
events = drvr._get_neutron_events(network_info, reboot=True)
self.assertEqual([('network-vif-plugged', '1'),
('network-vif-plugged', '2'),
('network-vif-plugged', '4')], events)
def test_unplug_vifs_ignores_errors(self):
drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI())
with mock.patch.object(drvr, 'vif_driver') as vif_driver:

@ -2550,14 +2550,9 @@ class LibvirtDriver(driver.ComputeDriver):
# Initialize all the necessary networking, block devices and
# start the instance.
# NOTE(melwitt): Pass vifs_already_plugged=True here even though we've
# unplugged vifs earlier. The behavior of neutron plug events depends
# on which vif type we're using and we are working with a stale network
# info cache here, so won't rely on waiting for neutron plug events.
# vifs_already_plugged=True means "do not wait for neutron plug events"
self._create_domain_and_network(context, xml, instance, network_info,
context, xml, instance, network_info,
block_device_info=block_device_info, reboot=True)
pci_manager.get_instance_pci_devs(instance, 'all'))
@ -5245,14 +5240,25 @@ class LibvirtDriver(driver.ComputeDriver):
if CONF.vif_plugging_is_fatal:
raise exception.VirtualInterfaceCreateException()
def _get_neutron_events(self, network_info):
# NOTE(danms): We need to collect any VIFs that are currently
# down that we expect a down->up event for. Anything that is
# already up will not undergo that transition, and for
# anything that might be stale (cache-wise) assume it's
# already up so we don't block on it.
def _get_neutron_events(self, network_info, reboot=False):
def eventable(vif):
if reboot:
# NOTE(melwitt): We won't expect events for the bridge vif
# type during a reboot because the neutron agent might not
# detect that we have unplugged and plugged vifs with os-vif.
# We also disregard the 'active' status of the vif during a
# reboot because the stale network_info we get from the compute
# manager won't show active=False for the vifs we've unplugged.
return vif.get('type') != network_model.VIF_TYPE_BRIDGE
# NOTE(danms): We need to collect any VIFs that are currently
# down that we expect a down->up event for. Anything that is
# already up will not undergo that transition, and for
# anything that might be stale (cache-wise) assume it's
# already up so we don't block on it.
return vif.get('active', True) is False
return [('network-vif-plugged', vif['id'])
for vif in network_info if vif.get('active', True) is False]
for vif in network_info if eventable(vif)]
def _cleanup_failed_start(self, context, instance, network_info,
block_device_info, guest, destroy_disks):
@ -5266,11 +5272,31 @@ class LibvirtDriver(driver.ComputeDriver):
def _create_domain_and_network(self, context, xml, instance, network_info,
power_on=True, reboot=False,
"""Do required network setup and create domain.
:param context: nova.context.RequestContext for volume API calls
:param xml: Guest domain XML
:param instance: nova.objects.Instance object
:param network_info: for the instance
:param block_device_info: Legacy block device info dict
:param power_on: Whether to power on the guest after creating the XML
:param vifs_already_plugged: False means "wait for neutron plug events"
if using neutron, qemu/kvm, power_on=True,
and CONF.vif_plugging_timeout configured
:param post_xml_callback: Optional callback to call after creating the
guest domain XML
:param destroy_disks_on_failure: Whether to destroy the disks if we
fail during guest domain creation
:param reboot: Whether or not this is being called during a reboot. If
we are rebooting, we will need to handle waiting for
neutron plug events differently
"""Do required network setup and create domain."""
block_device_mapping = driver.block_device_info_get_mapping(
@ -5293,7 +5319,7 @@ class LibvirtDriver(driver.ComputeDriver):
if (self._conn_supports_start_paused and
utils.is_neutron() and not
vifs_already_plugged and power_on and timeout):
events = self._get_neutron_events(network_info)
events = self._get_neutron_events(network_info, reboot=reboot)
events = []