diff --git a/contrib/rackspace/rackspace/resources/auto_scale.py b/contrib/rackspace/rackspace/resources/auto_scale.py
index b48ef2e130..d9a6b1ecaa 100644
--- a/contrib/rackspace/rackspace/resources/auto_scale.py
+++ b/contrib/rackspace/rackspace/resources/auto_scale.py
@@ -148,12 +148,18 @@ class Group(resource.Resource):
                 ),
                 LAUNCH_CONFIG_ARGS_SERVER_FLAVOR_REF: properties.Schema(
                     properties.Schema.STRING,
-                    _('Flavor ID.'),
+                    _('The ID or name of the flavor to boot onto.'),
+                    constraints=[
+                        constraints.CustomConstraint('nova.flavor')
+                    ],
                     required=True
                 ),
                 LAUNCH_CONFIG_ARGS_SERVER_IMAGE_REF: properties.Schema(
                     properties.Schema.STRING,
-                    _('Image ID.'),
+                    _('The ID or name of the image to boot with.'),
+                    constraints=[
+                        constraints.CustomConstraint('glance.image')
+                    ],
                     required=True
                 ),
                 LAUNCH_CONFIG_ARGS_SERVER_METADATA: properties.Schema(
@@ -298,12 +304,16 @@ class Group(resource.Resource):
         user_data = server_args.get(self.LAUNCH_CONFIG_ARGS_SERVER_USER_DATA)
         cdrive = (server_args.get(self.LAUNCH_CONFIG_ARGS_SERVER_CDRIVE) or
                   bool(user_data is not None and len(user_data.strip())))
+        image_id = self.client_plugin('glance').get_image_id(
+            server_args[self.LAUNCH_CONFIG_ARGS_SERVER_IMAGE_REF])
+        flavor_id = self.client_plugin('nova').get_flavor_id(
+            server_args[self.LAUNCH_CONFIG_ARGS_SERVER_FLAVOR_REF])
 
         return dict(
             launch_config_type=launchconf[self.LAUNCH_CONFIG_TYPE],
             server_name=server_args[self.GROUP_CONFIGURATION_NAME],
-            image=server_args[self.LAUNCH_CONFIG_ARGS_SERVER_IMAGE_REF],
-            flavor=server_args[self.LAUNCH_CONFIG_ARGS_SERVER_FLAVOR_REF],
+            image=image_id,
+            flavor=flavor_id,
             disk_config=server_args.get(
                 self.LAUNCH_CONFIG_ARGS_SERVER_DISK_CONFIG),
             metadata=server_args.get(self.GROUP_CONFIGURATION_METADATA),
diff --git a/contrib/rackspace/rackspace/tests/test_auto_scale.py b/contrib/rackspace/rackspace/tests/test_auto_scale.py
index bb0c834f2d..a2e30060b3 100644
--- a/contrib/rackspace/rackspace/tests/test_auto_scale.py
+++ b/contrib/rackspace/rackspace/tests/test_auto_scale.py
@@ -18,6 +18,8 @@ import mock
 
 from heat.common import exception
 from heat.common import template_format
+from heat.engine.clients.os import glance
+from heat.engine.clients.os import nova
 from heat.engine import resource
 from heat.engine import rsrc_defn
 from heat.engine import scheduler
@@ -207,6 +209,11 @@ class ScalingGroupTest(common.HeatTestCase):
         self.fake_auto_scale = FakeAutoScale()
         self.patchobject(auto_scale.Group, 'auto_scale',
                          return_value=self.fake_auto_scale)
+        # mock nova and glance client methods to satisfy contraints
+        mock_im = self.patchobject(glance.GlanceClientPlugin, 'get_image_id')
+        mock_im.return_value = 'image-ref'
+        mock_fl = self.patchobject(nova.NovaClientPlugin, 'get_flavor_id')
+        mock_fl.return_value = 'flavor-ref'
 
     def _setup_test_stack(self):
         self.stack = utils.parse_stack(self.group_template)