diff --git a/nova/scheduler/filters/aggregate_image_properties_isolation.py b/nova/scheduler/filters/aggregate_image_properties_isolation.py
index 461f91206..9974895c4 100644
--- a/nova/scheduler/filters/aggregate_image_properties_isolation.py
+++ b/nova/scheduler/filters/aggregate_image_properties_isolation.py
@@ -36,8 +36,10 @@ class AggregateImagePropertiesIsolation(filters.BaseHostFilter):
         """Checks a host in an aggregate that metadata key/value match
         with image properties.
         """
-        cfg_namespace = CONF.aggregate_image_properties_isolation_namespace
-        cfg_separator = CONF.aggregate_image_properties_isolation_separator
+        cfg_namespace = (CONF.filter_scheduler.
+            aggregate_image_properties_isolation_namespace)
+        cfg_separator = (CONF.filter_scheduler.
+            aggregate_image_properties_isolation_separator)
 
         image_props = spec_obj.image.properties if spec_obj.image else {}
         metadata = utils.aggregate_metadata_get_by_host(host_state)
diff --git a/nova/tests/unit/scheduler/filters/test_aggregate_image_properties_isolation_filters.py b/nova/tests/unit/scheduler/filters/test_aggregate_image_properties_isolation_filters.py
index 1a7ad672a..89b739b04 100644
--- a/nova/tests/unit/scheduler/filters/test_aggregate_image_properties_isolation_filters.py
+++ b/nova/tests/unit/scheduler/filters/test_aggregate_image_properties_isolation_filters.py
@@ -94,8 +94,10 @@ class TestAggImagePropsIsolationFilter(test.NoDBTestCase):
 
     def test_aggregate_image_properties_isolation_props_namespace(self,
             agg_mock):
-        self.flags(aggregate_image_properties_isolation_namespace="hw")
-        self.flags(aggregate_image_properties_isolation_separator="_")
+        self.flags(aggregate_image_properties_isolation_namespace='hw',
+                   group='filter_scheduler')
+        self.flags(aggregate_image_properties_isolation_separator='_',
+                   group='filter_scheduler')
         agg_mock.return_value = {'hw_vm_mode': 'hvm', 'img_owner_id': 'foo'}
         spec_obj = objects.RequestSpec(
             context=mock.sentinel.ctx,