Handle MissingAttributeError when using OOB inspections to fetch MACs

Currently, if an attempt is made to fetch MAC address information using
OOB inspection on a Redfish-managed node and EthernetInterfaces
attribute is missing on the node, inspection fails due to a
MissingAttributeError exception being raised by sushy. This change adds
catching and handling this exception.

Change-Id: I6f16da05e19c7efc966128fdf79f13546f51b5a6
(cherry picked from commit f10958a542)

ironic/drivers/modules/redfish/management.py

@@ -1197,9 +1197,18 @@ class RedfishManagement(base.ManagementInterface):
         :raises: RedfishError on an error from the Sushy library
         :returns: A list of MAC addresses for the node
         """
+        system = redfish_utils.get_system(task.node)
         try:
-            system = redfish_utils.get_system(task.node)
             return list(redfish_utils.get_enabled_macs(task, system))
+        # NOTE(janders) we should handle MissingAttributeError separately
+        # from other SushyErrors - some servers (e.g. some Cisco UCSB and UCSX
+        # blades) are missing EthernetInterfaces attribute yet could be
+        # provisioned successfully if MAC information is provided manually AND
+        # this exception is caught and handled accordingly.
+        except sushy.exceptions.MissingAttributeError as exc:
+            LOG.warning('Cannot get MAC addresses for node %(node)s: %(exc)s',
+                        {'node': task.node.uuid, 'exc': exc})
+        # if the exception is not a MissingAttributeError, raise it
         except sushy.exceptions.SushyError as exc:
             msg = (_('Failed to get network interface information on node '
                      '%(node)s: %(exc)s')

ironic/tests/unit/drivers/modules/redfish/test_management.py

@@ -1598,3 +1598,13 @@ class RedfishManagementTestCase(db_base.DbTestCase):
                                   shared=True) as task:
             self.assertEqual([],
                              task.driver.management.get_mac_addresses(task))
+
+    @mock.patch.object(redfish_utils, 'get_enabled_macs', autospec=True)
+    @mock.patch.object(redfish_utils, 'get_system', autospec=True)
+    def test_get_mac_addresses_missing_attr(self, mock_get_system,
+                                            mock_get_enabled_macs):
+        redfish_utils.get_enabled_macs.side_effect = (sushy.exceptions.
+                                                      MissingAttributeError)
+        with task_manager.acquire(self.context, self.node.uuid,
+                                  shared=True) as task:
+            self.assertIsNone(task.driver.management.get_mac_addresses(task))

releasenotes/notes/handle-missing-ethernetinterfaces-attr-7e52f7259fe66762.yaml

@@ -0,0 +1,9 @@
+---
+fixes:
+  - |
+    Fixes the bug where provisioning a Redfish managed node fails if the BMC
+    doesn't support EthernetInterfaces attribute, even if MAC address
+    information is provided manually. This is done by handling of
+    MissingAttributeError sushy exception in get_mac_addresses() method.
+    This fix is needed to successfully provision machines such as Cisco UCSB
+    and UCSX.