diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index aa816afea70b..904245c096f0 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -5413,10 +5413,11 @@ class ComputeManager(manager.Manager):
                 utils.get_image_from_system_metadata(
                     instance.system_metadata))
 
-        self.network_api.setup_instance_network_on_host(context, instance,
-                                                        self.host)
-        network_info = self.network_api.get_instance_nw_info(context, instance)
         try:
+            self.network_api.setup_instance_network_on_host(context, instance,
+                                                            self.host)
+            network_info = self.network_api.get_instance_nw_info(
+                context, instance)
             with rt.instance_claim(context, instance, node, limits):
                 self.driver.spawn(context, instance, image_meta,
                                   injected_files=[],
diff --git a/nova/tests/functional/regressions/test_bug_1862633.py b/nova/tests/functional/regressions/test_bug_1862633.py
index 03ef62041d2c..c04aa086c14e 100644
--- a/nova/tests/functional/regressions/test_bug_1862633.py
+++ b/nova/tests/functional/regressions/test_bug_1862633.py
@@ -58,7 +58,8 @@ class UnshelveNeutronErrorTest(
         }
         self.api.post_server_action(server['id'], req)
         self._wait_for_server_parameter(
-            self.api, server, {'status': 'SHELVED_OFFLOADED'})
+            self.api, server, {'status': 'SHELVED_OFFLOADED',
+                               'OS-EXT-SRV-ATTR:host': None})
         allocations = self.placement_api.get(
             '/allocations/%s' % server['id']).body['allocations']
         self.assertEqual(0, len(allocations))
@@ -84,14 +85,10 @@ class UnshelveNeutronErrorTest(
                 self.api,
                 server,
                 {'status': 'SHELVED_OFFLOADED',
-                 'OS-EXT-STS:task_state': None})
+                 'OS-EXT-STS:task_state': None,
+                 'OS-EXT-SRV-ATTR:host': None})
 
         # As the instance went back to offloaded state we expect no allocation
-        # allocations = self.placement_api.get(
-        #     '/allocations/%s' % server['id']).body['allocations']
-        # self.assertEqual(0, len(allocations))
-        #
-        # but the allocation is leaked this is bug 1862633
         allocations = self.placement_api.get(
             '/allocations/%s' % server['id']).body['allocations']
-        self.assertEqual(1, len(allocations))
+        self.assertEqual(0, len(allocations))