diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index b3317db582db..a1fb80622cc2 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -8382,14 +8382,7 @@ class ComputeManager(manager.Manager):
         # Releasing vlan.
         # (not necessary in current implementation?)
 
-        network_info = None
-        try:
-            network_info = self.network_api.get_instance_nw_info(
-                ctxt, instance)
-        except Exception as e:
-            LOG.info('Unable to obtain network info: %s. Network info in '
-                     'live.migration._post.start notification will be '
-                     'omitted.', e, instance=instance)
+        network_info = self.network_api.get_instance_nw_info(ctxt, instance)
 
         self._notify_about_instance_usage(ctxt, instance,
                                           "live_migration._post.start",
diff --git a/nova/tests/functional/compute/test_live_migration.py b/nova/tests/functional/compute/test_live_migration.py
index d64c49d711a8..57965ae24097 100644
--- a/nova/tests/functional/compute/test_live_migration.py
+++ b/nova/tests/functional/compute/test_live_migration.py
@@ -215,6 +215,10 @@ class LiveMigrationNeutronFailure(integrated_helpers._IntegratedTestBase):
         with mock.patch.object(self.computes['src'].manager,
                                '_post_live_migration',
                                side_effect=stub_plm):
-            self._live_migrate(server, 'completed')
+            # FIXME(artom) Until bug 1879787 is fixed, the raised
+            # ConnectionError will go unhandled, the migration will fail, and
+            # the instance will still be reported as being on the source, even
+            # though it's actually running on the destination.
+            self._live_migrate(server, 'error', server_expected_state='ERROR')
             server = self.api.get_server(server['id'])
-            self.assertEqual('dest', server['OS-EXT-SRV-ATTR:host'])
+            self.assertEqual('src', server['OS-EXT-SRV-ATTR:host'])