openstack/nova
Code Issues Proposed changes

libvirt: disconnect volume from host during detach

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Under certain failure scenarios it may be that although the libvirt
definition for the volume has been removed for the instance that the
associated storage lun on the compute server may not have been fully
cleaned up yet.

In case users try an other attempt to detach volume we should not stop
the process whether the device is not found in domain definition but
try to disconnect the logical device from host.

This commit makes the process to attempt a disconnect volume even if
the device is not attached to the guest.

Closes-Bug: #1727260
Change-Id: I4182642aab3fd2ffb1c97d2de9bdca58982289d8
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@redhat.com>
This commit is contained in:
Sahid Orentino Ferdjaoui 2017-10-25 05:57:11 -04:00 committed by sahid
parent 4a03e3e5d4
commit ce531dd1b7
2 changed files with 41 additions and 4 deletions
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39
nova/tests/unit/virt/libvirt/test_driver.py
View File

@ -6913,8 +6913,10 @@ class LibvirtConnTestCase(test.NoDBTestCase,
mock_disconnect_volume.assert_called_with(
None, connection_info, instance, encryption=None)
@mock.patch('nova.virt.libvirt.driver.LibvirtDriver._disconnect_volume')
@mock.patch('nova.virt.libvirt.host.Host._get_domain')
def test_detach_volume_disk_not_found(self, mock_get_domain):
def test_detach_volume_disk_not_found(self, mock_get_domain,
mock_disconnect_volume):
drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
instance = objects.Instance(**self.test_instance)
mock_xml_without_disk = """<domain>
@ -6930,10 +6932,41 @@ class LibvirtConnTestCase(test.NoDBTestCase,
mock_dom.info.return_value = [power_state.RUNNING, 512, 512, 2, 1234,
5678]
mock_get_domain.return_value = mock_dom
self.assertRaises(exception.DiskNotFound, drvr.detach_volume,
connection_info, instance, '/dev/vdc')
drvr.detach_volume(connection_info, instance, '/dev/vdc')
mock_get_domain.assert_called_once_with(instance)
mock_disconnect_volume.assert_called_once_with(
None, connection_info, instance, encryption=None)
@mock.patch('nova.virt.libvirt.driver.LibvirtDriver._get_volume_encryptor')
@mock.patch('nova.virt.libvirt.driver.LibvirtDriver._disconnect_volume')
@mock.patch('nova.virt.libvirt.host.Host._get_domain')
def test_detach_volume_disk_not_found_encryption(self, mock_get_domain,
mock_disconnect_volume,
mock_get_encryptor):
drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
instance = objects.Instance(**self.test_instance)
mock_xml_without_disk = """<domain>
<devices>
</devices>
</domain>"""
mock_dom = mock.MagicMock(return_value=mock_xml_without_disk)
encryption = mock.MagicMock()
connection_info = {"driver_volume_type": "fake",
"data": {"device_path": "/fake",
"access_mode": "rw"}}
mock_dom.info.return_value = [power_state.RUNNING, 512, 512, 2, 1234,
5678]
mock_get_domain.return_value = mock_dom
drvr.detach_volume(connection_info, instance, '/dev/vdc',
encryption)
mock_disconnect_volume.assert_called_once_with(
None, connection_info, instance, encryption=encryption)
@mock.patch('nova.virt.libvirt.driver.LibvirtDriver._get_volume_driver')
@mock.patch('nova.virt.libvirt.driver.LibvirtDriver._get_volume_encryptor')

6
nova/virt/libvirt/driver.py
View File

@ -1568,7 +1568,11 @@ class LibvirtDriver(driver.ComputeDriver):
LOG.warning("During detach_volume, instance disappeared.",
instance=instance)
except exception.DeviceNotFound:
raise exception.DiskNotFound(location=disk_dev)
# We should still try to disconnect logical device from
# host, an error might have happened during a previous
# call.
LOG.info("Device %s not found in instance.",
disk_dev, instance=instance)
except libvirt.libvirtError as ex:
# NOTE(vish): This is called to cleanup volumes after live
# migration, so we should still disconnect even if