diff --git a/ceilometer/gnocchi_client.py b/ceilometer/gnocchi_client.py
index e2ea7e1016..2effbdfb7b 100644
--- a/ceilometer/gnocchi_client.py
+++ b/ceilometer/gnocchi_client.py
@@ -258,8 +258,8 @@ def upgrade_resource_types(conf):
 
     gnocchi_version = version.LooseVersion(gnocchi.build.get())
     if gnocchi_version < REQUIRED_VERSION:
-        raise Exception("required gnocchi version is %s, got %s",
-                        REQUIRED_VERSION, gnocchi_version)
+        raise Exception("required gnocchi version is %s, got %s" %
+                        (REQUIRED_VERSION, gnocchi_version))
 
     for name, attributes in resources_initial.items():
         try: