Check our nodes for hypervisor_hostname changes

When we are loading our ComputeNode objects by UUID according to what
the virt driver reported, we can sanity check the DB records against
the virt driver's hostname. This covers the case where our CONF.host
has not changed but the hostname reported by the virt driver has,
assuming we can find the ComputeNode object(s) that match our
persistent node uuid.

Related to blueprint stable-compute-uuid
Change-Id: I41635210d7d6f46b437b06d2570a26a80ed8676a

1 files changed, 36 insertions, 12 deletions

diff --git a/nova/tests/unit/compute/test_compute_mgr.py b/nova/tests/unit/compute/test_compute_mgr.py
index c923b0e967..c5fed20377 100644
--- a/nova/tests/unit/compute/test_compute_mgr.py
+++ b/nova/tests/unit/compute/test_compute_mgr.py
@@ -1162,24 +1162,48 @@ class ComputeManagerUnitTestCase(test.NoDBTestCase,
             mock_get_nodes.return_value.keys())
 
     @mock.patch.object(objects.ComputeNodeList, 'get_all_by_uuids')
-    @mock.patch.object(fake_driver.FakeDriver, 'get_available_nodes')
+    @mock.patch.object(fake_driver.FakeDriver, 'get_nodenames_by_uuid')
     def test_get_nodes(self, mock_driver_get_nodes, mock_get_by_uuid):
-        mock_driver_get_nodes.return_value = ['fake_node1', 'fake_node2']
+        mock_driver_get_nodes.return_value = {uuids.node_fake_node1: 'host',
+                                              uuids.node_fake_node2: 'host'}
         # NOTE(danms): The fake driver, by default, uses
-        # uuidsentinel.$node_name, so we can predict the uuids it will
+        # uuidsentinel.node_$node_name, so we can predict the uuids it will
         # return here.
-        cn1 = objects.ComputeNode(uuid=uuids.fake_node1)
-        cn2 = objects.ComputeNode(uuid=uuids.fake_node2)
+        cn1 = objects.ComputeNode(uuid=uuids.node_fake_node1,
+                                  hypervisor_hostname='host')
+        cn2 = objects.ComputeNode(uuid=uuids.node_fake_node2,
+                                  hypervisor_hostname='host')
         mock_get_by_uuid.return_value = [cn1, cn2]
 
         nodes = self.compute._get_nodes(self.context)
 
-        self.assertEqual({uuids.fake_node1: cn1, uuids.fake_node2: cn2}, nodes)
+        self.assertEqual({uuids.node_fake_node1: cn1,
+                          uuids.node_fake_node2: cn2}, nodes)
 
         mock_driver_get_nodes.assert_called_once_with()
         mock_get_by_uuid.assert_called_once_with(self.context,
-                                                 [uuids.fake_node1,
-                                                  uuids.fake_node2])
+                                                 [uuids.node_fake_node1,
+                                                  uuids.node_fake_node2])
+
+    @mock.patch.object(objects.ComputeNodeList, 'get_all_by_uuids')
+    @mock.patch.object(fake_driver.FakeDriver, 'get_nodenames_by_uuid')
+    def test_get_nodes_mismatch(self, mock_driver_get_nodes, mock_get_by_uuid):
+        # Virt driver reports a (hypervisor_) hostname of 'host1'
+        mock_driver_get_nodes.return_value = {uuids.node_fake_node1: 'host1',
+                                              uuids.node_fake_node2: 'host1'}
+
+        # The database records for our compute nodes (by UUID) show a
+        # hypervisor_hostname of 'host2'
+        cn1 = objects.ComputeNode(uuid=uuids.node_fake_node1,
+                                  hypervisor_hostname='host2')
+        cn2 = objects.ComputeNode(uuid=uuids.node_fake_node2,
+                                  hypervisor_hostname='host2')
+        mock_get_by_uuid.return_value = [cn1, cn2]
+
+        # Possible hostname (as reported by the virt driver) rename,
+        # which should abort our startup
+        self.assertRaises(exception.InvalidConfiguration,
+                          self.compute._get_nodes, self.context)
 
     @mock.patch.object(manager.LOG, 'warning')
     @mock.patch.object(
@@ -1202,11 +1226,11 @@ class ComputeManagerUnitTestCase(test.NoDBTestCase,
 
     @mock.patch.object(manager.LOG, 'warning')
     @mock.patch.object(objects.ComputeNodeList, 'get_all_by_uuids')
-    @mock.patch.object(fake_driver.FakeDriver, 'get_available_node_uuids')
+    @mock.patch.object(fake_driver.FakeDriver, 'get_nodenames_by_uuid')
     def test_get_nodes_node_not_found(
             self, mock_driver_get_nodes, mock_get_all_by_uuids,
             mock_log_warning):
-        mock_driver_get_nodes.return_value = ['fake-node1']
+        mock_driver_get_nodes.return_value = {uuids.node_1: 'fake-node1'}
         mock_get_all_by_uuids.return_value = []
 
         nodes = self.compute._get_nodes(self.context)
@@ -1215,11 +1239,11 @@ class ComputeManagerUnitTestCase(test.NoDBTestCase,
 
         mock_driver_get_nodes.assert_called_once_with()
         mock_get_all_by_uuids.assert_called_once_with(self.context,
-                                                      ['fake-node1'])
+                                                      [uuids.node_1])
         mock_log_warning.assert_called_once_with(
             "Compute nodes %s for host %s were not found in the database. "
             "If this is the first time this service is starting on this host, "
-            "then you can ignore this warning.", ['fake-node1'], 'fake-mini')
+            "then you can ignore this warning.", [uuids.node_1], 'fake-mini')
 
     def test_init_host_disk_devices_configuration_failure(self):
         self.flags(max_disk_devices_to_attach=0, group='compute')