iSCSI: Fix flushing after multipath cfg change

OS-Brick disconnect_volume code assumes that the use_multipath parameter
that is used to instantiate the connector has the same value than the
connector that was used on the original connect_volume call.

Unfortunately this is not necessarily true, because Nova can attach a
volume, then its multipath configuration can be enabled or disabled, and
then a detach can be issued.

This leads to a series of serious issues such as:

- Not flushing the single path on disconnect_volume (possible data loss)
  and leaving it as a leftover device on the host when Nova calls
  terminate-connection on Cinder.

- Not flushing the multipath device (possible data loss) and leaving it
  as a leftover device similarly to the other case.

This patch changes how we do disconnects, now we assume we are always
disconnecting multipaths, and fallback to doing the single path
disconnect we used to do if we can't go that route.

The case when we cannot do a multipathed detach is mostly when we did
the connect as a single path and the Cinder driver doesn't provide
portal_targets and portal_iqns in the connection info for non
multipathed initialize-connection calls.

This changes introduces an additional call when working with single
paths (checking the discoverydb), but it should be an acceptable
trade-off to not lose data.

Also includes squash to add release note from:
Add release note prelude for os-brick 4.4.0
Change-Id: I0f9e088fbb14ee9a73175aa31bca8c619db5a96f

Closes-Bug: #1921381
Change-Id: I066d456fb1fe9159d4be50ffd8abf9a6d8d07901
(cherry picked from commit d4205bd0be)
(cherry picked from commit c70d70b240)

os_brick/exception.py

@@ -120,7 +120,7 @@ class TargetPortalNotFound(BrickException):
     message = _("Unable to find target portal %(target_portal)s.")
 
 
-class TargetPortalsNotFound(BrickException):
+class TargetPortalsNotFound(TargetPortalNotFound):
     message = _("Unable to find target portal in %(target_portals)s.")
 
 

os_brick/initiator/connectors/base_iscsi.py

@@ -29,13 +29,18 @@ class BaseISCSIConnector(initiator_connector.InitiatorConnector):
                 props.pop(key, None)
             yield props
 
+    @staticmethod
+    def _get_luns(con_props, iqns=None):
+        luns = con_props.get('target_luns')
+        num_luns = len(con_props['target_iqns']) if iqns is None else len(iqns)
+        return luns or [con_props['target_lun']] * num_luns
+
     def _get_all_targets(self, connection_properties):
-        if all([key in connection_properties for key in ('target_portals',
-                                                         'target_iqns',
-                                                         'target_luns')]):
-            return zip(connection_properties['target_portals'],
-                       connection_properties['target_iqns'],
-                       connection_properties['target_luns'])
+        if all(key in connection_properties for key in ('target_portals',
+                                                        'target_iqns')):
+            return list(zip(connection_properties['target_portals'],
+                            connection_properties['target_iqns'],
+                            self._get_luns(connection_properties)))
 
         return [(connection_properties['target_portal'],
                  connection_properties['target_iqn'],

os_brick/initiator/connectors/iscsi.py

@@ -167,35 +167,45 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
         # entry: [tcp, [1], 192.168.121.250:3260,1 ...]
         return [entry[2] for entry in self._get_iscsi_sessions_full()]
 
-    def _get_ips_iqns_luns(self, connection_properties, discover=True):
+    def _get_ips_iqns_luns(self, connection_properties, discover=True,
+                           is_disconnect_call=False):
         """Build a list of ips, iqns, and luns.
 
-        Used only when doing multipath, we have 3 cases:
+        Used when doing singlepath and multipath, and we have 4 cases:
 
         - All information is in the connection properties
         - We have to do an iSCSI discovery to get the information
         - We don't want to do another discovery and we query the discoverydb
+        - Discovery failed because it was actually a single pathed attachment
 
         :param connection_properties: The dictionary that describes all
                                       of the target volume attributes.
         :type connection_properties: dict
         :param discover: Whether doing an iSCSI discovery is acceptable.
         :type discover: bool
+        :param is_disconnect_call: Whether this is a call coming from a user
+                                   disconnect_volume call or a call from some
+                                   other operation's cleanup.
+        :type is_disconnect_call: bool
         :returns: list of tuples of (ip, iqn, lun)
         """
+        # There are cases where we don't know if the local attach was done
+        # using multipathing or single pathing, so assume multipathing.
         try:
             if ('target_portals' in connection_properties and
                     'target_iqns' in connection_properties):
                 # Use targets specified by connection_properties
-                ips_iqns_luns = list(
-                    zip(connection_properties['target_portals'],
-                        connection_properties['target_iqns'],
-                        self._get_luns(connection_properties)))
+                ips_iqns_luns = self._get_all_targets(connection_properties)
             else:
                 method = (self._discover_iscsi_portals if discover
                           else self._get_discoverydb_portals)
                 ips_iqns_luns = method(connection_properties)
-        except exception.TargetPortalsNotFound:
+        except exception.TargetPortalNotFound:
+            # Discovery failed, on disconnect this will happen if we
+            # are detaching a single pathed connection, so we use the
+            # connection properties to return the tuple.
+            if is_disconnect_call:
+                return self._get_all_targets(connection_properties)
             raise
         except Exception:
             LOG.exception('Exception encountered during portal discovery')
@@ -311,12 +321,6 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
     def _get_transport(self):
         return self.transport
 
-    @staticmethod
-    def _get_luns(con_props, iqns=None):
-        luns = con_props.get('target_luns')
-        num_luns = len(con_props['target_iqns']) if iqns is None else len(iqns)
-        return luns or [con_props.get('target_lun')] * num_luns
-
     def _get_discoverydb_portals(self, connection_properties):
         """Retrieve iscsi portals information from the discoverydb.
 
@@ -787,7 +791,7 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
                                         mpath)
 
     def _get_connection_devices(self, connection_properties,
-                                ips_iqns_luns=None):
+                                ips_iqns_luns=None, is_disconnect_call=False):
         """Get map of devices by sessions from our connection.
 
         For each of the TCP sessions that correspond to our connection
@@ -807,14 +811,15 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
         connection properties (sendtargets was used on connect) so we may have
         to retrieve the info from the discoverydb.  Call _get_ips_iqns_luns to
         do the right things.
+
+        This method currently assumes that it's only called by the
+        _cleanup_conection method.
         """
         if not ips_iqns_luns:
-            if self.use_multipath:
-                # We are only called from disconnect, so don't discover
-                ips_iqns_luns = self._get_ips_iqns_luns(connection_properties,
-                                                        discover=False)
-            else:
-                ips_iqns_luns = self._get_all_targets(connection_properties)
+            # This is a cleanup, don't do discovery
+            ips_iqns_luns = self._get_ips_iqns_luns(
+                connection_properties, discover=False,
+                is_disconnect_call=is_disconnect_call)
         LOG.debug('Getting connected devices for (ips,iqns,luns)=%s',
                   ips_iqns_luns)
         nodes = self._get_iscsi_nodes()
@@ -874,11 +879,12 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
         """
         return self._cleanup_connection(connection_properties, force=force,
                                         ignore_errors=ignore_errors,
-                                        device_info=device_info)
+                                        device_info=device_info,
+                                        is_disconnect_call=True)
 
     def _cleanup_connection(self, connection_properties, ips_iqns_luns=None,
                             force=False, ignore_errors=False,
-                            device_info=None):
+                            device_info=None, is_disconnect_call=False):
         """Cleans up connection flushing and removing devices and multipath.
 
         :param connection_properties: The dictionary that describes all
@@ -895,13 +901,18 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
                               ignore errors or raise an exception once finished
                               the operation.  Default is False.
         :param device_info: Attached device information.
+        :param is_disconnect_call: Whether this is a call coming from a user
+                                   disconnect_volume call or a call from some
+                                   other operation's cleanup.
+        :type is_disconnect_call: bool
         :type ignore_errors: bool
         """
         exc = exception.ExceptionChainer()
         try:
             devices_map = self._get_connection_devices(connection_properties,
-                                                       ips_iqns_luns)
-        except exception.TargetPortalsNotFound as exc:
+                                                       ips_iqns_luns,
+                                                       is_disconnect_call)
+        except exception.TargetPortalNotFound as exc:
             # When discovery sendtargets failed on connect there is no
             # information in the discoverydb, so there's nothing to clean.
             LOG.debug('Skipping cleanup %s', exc)
@@ -917,8 +928,7 @@ class ISCSIConnector(base.BaseLinuxConnector, base_iscsi.BaseISCSIConnector):
         was_multipath = (path_used.startswith('/dev/dm-') or
                          'mpath' in path_used)
         multipath_name = self._linuxscsi.remove_connection(
-            remove_devices, self.use_multipath, force, exc,
-            path_used, was_multipath)
+            remove_devices, force, exc, path_used, was_multipath)
 
         # Disconnect sessions and remove nodes that are left without devices
         disconnect = [conn for conn, (__, keep) in devices_map.items()

os_brick/initiator/linuxscsi.py

@@ -288,12 +288,11 @@ class LinuxSCSI(executor.Executor):
         # instead it maps to /dev/mapped/crypt-XYZ
         return not was_multipath and '/dev' != os.path.split(path_used)[0]
 
-    def remove_connection(self, devices_names, is_multipath, force=False,
-                          exc=None, path_used=None, was_multipath=False):
+    def remove_connection(self, devices_names, force=False, exc=None,
+                          path_used=None, was_multipath=False):
         """Remove LUNs and multipath associated with devices names.
 
         :param devices_names: Iterable with real device names ('sda', 'sdb')
-        :param is_multipath: Whether this is a multipath connection or not
         :param force: Whether to forcefully disconnect even if flush fails.
         :param exc: ExceptionChainer where to add exceptions if forcing
         :param path_used: What path was used by Nova/Cinder for I/O
@@ -302,19 +301,17 @@ class LinuxSCSI(executor.Executor):
         """
         if not devices_names:
             return
-        multipath_name = None
         exc = exception.ExceptionChainer() if exc is None else exc
-        LOG.debug('Removing %(type)s devices %(devices)s',
-                  {'type': 'multipathed' if is_multipath else 'single pathed',
-                   'devices': ', '.join(devices_names)})
 
-        if is_multipath:
-            multipath_dm = self.find_sysfs_multipath_dm(devices_names)
-            multipath_name = multipath_dm and self.get_dm_name(multipath_dm)
-            if multipath_name:
-                with exc.context(force, 'Flushing %s failed', multipath_name):
-                    self.flush_multipath_device(multipath_name)
-                    multipath_name = None
+        multipath_dm = self.find_sysfs_multipath_dm(devices_names)
+        LOG.debug('Removing %(type)s devices %(devices)s',
+                  {'type': 'multipathed' if multipath_dm else 'single pathed',
+                   'devices': ', '.join(devices_names)})
+        multipath_name = multipath_dm and self.get_dm_name(multipath_dm)
+        if multipath_name:
+            with exc.context(force, 'Flushing %s failed', multipath_name):
+                self.flush_multipath_device(multipath_name)
+                multipath_name = None
 
         for device_name in devices_names:
             dev_path = '/dev/' + device_name

os_brick/tests/initiator/connectors/test_base_iscsi.py

@@ -51,16 +51,29 @@ class BaseISCSIConnectorTestCase(test_base.TestCase):
         self.assertEqual(expected_props, list_props[0])
 
     def test_get_all_targets(self):
-        connection_properties = {
-            'target_portals': [mock.sentinel.target_portals],
-            'target_iqns': [mock.sentinel.target_iqns],
-            'target_luns': [mock.sentinel.target_luns]}
+        portals = [mock.sentinel.portals1, mock.sentinel.portals2]
+        iqns = [mock.sentinel.iqns1, mock.sentinel.iqns2]
+        luns = [mock.sentinel.luns1, mock.sentinel.luns2]
+        connection_properties = {'target_portals': portals,
+                                 'target_iqns': iqns,
+                                 'target_luns': luns}
 
         all_targets = self.connector._get_all_targets(connection_properties)
 
-        expected_targets = zip([mock.sentinel.target_portals],
-                               [mock.sentinel.target_iqns],
-                               [mock.sentinel.target_luns])
+        expected_targets = zip(portals, iqns, luns)
+        self.assertEqual(list(expected_targets), list(all_targets))
+
+    def test_get_all_targets_no_target_luns(self):
+        portals = [mock.sentinel.portals1, mock.sentinel.portals2]
+        iqns = [mock.sentinel.iqns1, mock.sentinel.iqns2]
+        lun = mock.sentinel.luns
+        connection_properties = {'target_portals': portals,
+                                 'target_iqns': iqns,
+                                 'target_lun': lun}
+
+        all_targets = self.connector._get_all_targets(connection_properties)
+
+        expected_targets = zip(portals, iqns, [lun, lun])
         self.assertEqual(list(expected_targets), list(all_targets))
 
     def test_get_all_targets_single_target(self):

os_brick/tests/initiator/connectors/test_iscsi.py

@@ -140,7 +140,6 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
     @mock.patch.object(iscsi.ISCSIConnector, '_get_iscsi_nodes')
     def test_get_connection_devices(self, nodes_mock, sessions_mock,
                                     glob_mock, iql_mock):
-        self.connector.use_multipath = True
         iql_mock.return_value = self.connector._get_all_targets(self.CON_PROPS)
 
         # List sessions from other targets and non tcp sessions
@@ -166,7 +165,8 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
                     ('ip2:port2', 'tgt2'): ({'sdb'}, {'sdc'}),
                     ('ip3:port3', 'tgt3'): (set(), set())}
         self.assertDictEqual(expected, res)
-        iql_mock.assert_called_once_with(self.CON_PROPS, discover=False)
+        iql_mock.assert_called_once_with(self.CON_PROPS, discover=False,
+                                         is_disconnect_call=False)
 
     @mock.patch('glob.glob')
     @mock.patch.object(iscsi.ISCSIConnector, '_get_iscsi_sessions_full')
@@ -560,7 +560,8 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
             mock.sentinel.con_props,
             force=mock.sentinel.Force,
             ignore_errors=mock.sentinel.ignore_errors,
-            device_info=mock.sentinel.dev_info)
+            device_info=mock.sentinel.dev_info,
+            is_disconnect_call=True)
 
     @ddt.data(True, False)
     @mock.patch.object(iscsi.ISCSIConnector, '_get_transport')
@@ -692,19 +693,17 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
             (('ip2:port2', 'tgt2'), ({'sdb'}, {'sdc'})),
             (('ip3:port3', 'tgt3'), (set(), set()))))
 
-        with mock.patch.object(self.connector,
-                               'use_multipath') as use_mp_mock:
-            self.connector._cleanup_connection(
-                self.CON_PROPS, ips_iqns_luns=mock.sentinel.ips_iqns_luns,
-                force=False, ignore_errors=False,
-                device_info=mock.sentinel.device_info)
+        self.connector._cleanup_connection(
+            self.CON_PROPS, ips_iqns_luns=mock.sentinel.ips_iqns_luns,
+            force=False, ignore_errors=False,
+            device_info=mock.sentinel.device_info)
 
         get_dev_path_mock.called_once_with(self.CON_PROPS,
                                            mock.sentinel.device_info)
         con_devs_mock.assert_called_once_with(self.CON_PROPS,
-                                              mock.sentinel.ips_iqns_luns)
-        remove_mock.assert_called_once_with({'sda', 'sdb'}, use_mp_mock,
-                                            False, mock.ANY,
+                                              mock.sentinel.ips_iqns_luns,
+                                              False)
+        remove_mock.assert_called_once_with({'sda', 'sdb'}, False, mock.ANY,
                                             path_used, was_multipath)
         discon_mock.assert_called_once_with(
             self.CON_PROPS,
@@ -730,17 +729,16 @@ class ISCSIConnectorTestCase(test_connector.ConnectorTestCase):
             (('ip2:port2', 'tgt2'), ({'sdb'}, {'sdc'})),
             (('ip3:port3', 'tgt3'), (set(), set()))))
 
-        with mock.patch.object(self.connector, 'use_multipath',
-                               wraps=True) as use_mp_mock:
-            self.assertRaises(exception.ExceptionChainer,
-                              self.connector._cleanup_connection,
-                              self.CON_PROPS,
-                              ips_iqns_luns=mock.sentinel.ips_iqns_luns,
-                              force=mock.sentinel.force, ignore_errors=False)
+        self.assertRaises(exception.ExceptionChainer,
+                          self.connector._cleanup_connection,
+                          self.CON_PROPS,
+                          ips_iqns_luns=mock.sentinel.ips_iqns_luns,
+                          force=mock.sentinel.force, ignore_errors=False)
 
         con_devs_mock.assert_called_once_with(self.CON_PROPS,
-                                              mock.sentinel.ips_iqns_luns)
-        remove_mock.assert_called_once_with({'sda', 'sdb'}, use_mp_mock,
+                                              mock.sentinel.ips_iqns_luns,
+                                              False)
+        remove_mock.assert_called_once_with({'sda', 'sdb'},
                                             mock.sentinel.force, mock.ANY,
                                             '', False)
         discon_mock.assert_called_once_with(
@@ -976,6 +974,21 @@ Setting up iSCSI targets: unused
         db_portals_mock.assert_called_once_with(self.SINGLE_CON_PROPS)
         discover_mock.assert_not_called()
 
+    @mock.patch.object(iscsi.ISCSIConnector, '_get_all_targets')
+    @mock.patch.object(iscsi.ISCSIConnector, '_get_discoverydb_portals')
+    @mock.patch.object(iscsi.ISCSIConnector, '_discover_iscsi_portals')
+    def test_get_ips_iqns_luns_disconnect_single_path(self, discover_mock,
+                                                      db_portals_mock,
+                                                      get_targets_mock):
+        db_portals_mock.side_effect = exception.TargetPortalsNotFound
+        res = self.connector._get_ips_iqns_luns(self.SINGLE_CON_PROPS,
+                                                discover=False,
+                                                is_disconnect_call=True)
+        db_portals_mock.assert_called_once_with(self.SINGLE_CON_PROPS)
+        discover_mock.assert_not_called()
+        get_targets_mock.assert_called_once_with(self.SINGLE_CON_PROPS)
+        self.assertEqual(get_targets_mock.return_value, res)
+
     @mock.patch.object(iscsi.ISCSIConnector, '_discover_iscsi_portals')
     def test_get_ips_iqns_luns_no_target_iqns_share_iqn(self, discover_mock):
         discover_mock.return_value = [('ip1:port1', 'tgt1', '1'),
@@ -1249,7 +1262,9 @@ Setting up iSCSI targets: unused
 
         connect_mock.side_effect = my_connect
 
-        res = self.connector._connect_multipath_volume(self.CON_PROPS)
+        with mock.patch.object(self.connector,
+                               'use_multipath'):
+            res = self.connector._connect_multipath_volume(self.CON_PROPS)
 
         expected = {'type': 'block', 'scsi_wwn': '', 'multipath_id': '',
                     'path': '/dev/dm-0'}

os_brick/tests/initiator/connectors/test_iser.py

@@ -56,7 +56,8 @@ class ISERConnectorTestCase(test_connector.ConnectorTestCase):
         res = self.connector._get_connection_devices(self.connection_data)
         expected = {('ip:port', 'target_1'): ({'sda'}, set())}
         self.assertDictEqual(expected, res)
-        iql_mock.assert_called_once_with(self.connection_data, discover=False)
+        iql_mock.assert_called_once_with(self.connection_data, discover=False,
+                                         is_disconnect_call=False)
 
     @mock.patch.object(iscsi.ISCSIConnector, '_get_iscsi_sessions_full')
     @mock.patch.object(iscsi.ISCSIConnector, '_execute')

os_brick/tests/initiator/test_linuxscsi.py

@@ -245,7 +245,6 @@ class LinuxSCSITestCase(base.TestCase):
         devices_names = ('sda', 'sdb')
         exc = exception.ExceptionChainer()
         mp_name = self.linuxscsi.remove_connection(devices_names,
-                                                   is_multipath=True,
                                                    force=mock.sentinel.Force,
                                                    exc=exc)
         find_dm_mock.assert_called_once_with(devices_names)
@@ -275,8 +274,7 @@ class LinuxSCSITestCase(base.TestCase):
         exc = exception.ExceptionChainer()
         self.assertRaises(exception.ExceptionChainer,
                           self.linuxscsi.remove_connection,
-                          devices_names, is_multipath=True,
-                          force=False, exc=exc)
+                          devices_names, force=False, exc=exc)
         find_dm_mock.assert_called_once_with(devices_names)
         get_dm_name_mock.assert_called_once_with(find_dm_mock.return_value)
         flush_mp_mock.assert_called_once_with(get_dm_name_mock.return_value)
@@ -285,36 +283,49 @@ class LinuxSCSITestCase(base.TestCase):
         remove_link_mock.assert_not_called()
         self.assertTrue(bool(exc))
 
+    @mock.patch.object(linuxscsi.LinuxSCSI, 'find_sysfs_multipath_dm')
     @mock.patch.object(linuxscsi.LinuxSCSI, '_remove_scsi_symlinks')
     @mock.patch.object(linuxscsi.LinuxSCSI, 'wait_for_volumes_removal')
     @mock.patch.object(linuxscsi.LinuxSCSI, 'remove_scsi_device')
-    def test_remove_connection_singlepath(self, remove_mock, wait_mock,
-                                          remove_link_mock):
+    def test_remove_connection_singlepath_no_path(self, remove_mock, wait_mock,
+                                                  remove_link_mock,
+                                                  find_dm_mock):
+        # Test remove connection when we didn't form a multipath and didn't
+        # even use any of the devices that were found.  This means that we
+        # don't flush any of the single paths when removing them.
+        find_dm_mock.return_value = None
         devices_names = ('sda', 'sdb')
         exc = exception.ExceptionChainer()
-        self.linuxscsi.remove_connection(devices_names, is_multipath=False,
+        self.linuxscsi.remove_connection(devices_names,
                                          force=mock.sentinel.Force,
                                          exc=exc)
+        find_dm_mock.assert_called_once_with(devices_names)
         remove_mock.assert_has_calls(
             [mock.call('/dev/sda', mock.sentinel.Force, exc, False),
              mock.call('/dev/sdb', mock.sentinel.Force, exc, False)])
         wait_mock.assert_called_once_with(devices_names)
         remove_link_mock.assert_called_once_with(devices_names)
 
+    @mock.patch.object(linuxscsi.LinuxSCSI, 'find_sysfs_multipath_dm')
     @mock.patch.object(linuxscsi.LinuxSCSI, '_remove_scsi_symlinks')
     @mock.patch.object(linuxscsi.LinuxSCSI, 'wait_for_volumes_removal')
     @mock.patch.object(linuxscsi.LinuxSCSI, 'remove_scsi_device')
     def test_remove_connection_singlepath_used(self, remove_mock, wait_mock,
-                                               remove_link_mock):
+                                               remove_link_mock, find_dm_mock):
+        # Test remove connection when we didn't form a multipath and just used
+        # one of the single paths that were found.  This means that we don't
+        # flush any of the single paths when removing them.
+        find_dm_mock.return_value = None
         devices_names = ('sda', 'sdb')
         exc = exception.ExceptionChainer()
 
         # realpath was mocked on test setup
         with mock.patch('os.path.realpath', side_effect=self.realpath):
-            self.linuxscsi.remove_connection(devices_names, is_multipath=True,
+            self.linuxscsi.remove_connection(devices_names,
                                              force=mock.sentinel.Force,
                                              exc=exc, path_used='/dev/sdb',
                                              was_multipath=False)
+        find_dm_mock.assert_called_once_with(devices_names)
         remove_mock.assert_has_calls(
             [mock.call('/dev/sda', mock.sentinel.Force, exc, False),
              mock.call('/dev/sdb', mock.sentinel.Force, exc, True)])

releasenotes/notes/disconnect-multipath-cfg-changed-637abc5ecf44fb10.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    `Bug #1921381 <https://bugs.launchpad.net/cinder/+bug/1921381>`_: Fix
+    disconnecting volumes when the use_multipath value is changed from the
+    connect_volume call to the disconnect_volume call.

releasenotes/notes/wallaby-extra-prelude-d8de88e3e11a7b9f.yaml

@@ -0,0 +1,5 @@
+---
+prelude: >
+    This release fixes an issue that could cause data loss when the
+    configuration enabling/disabling multipathing is changed on a compute
+    when volumes are currently attached.