diff --git a/lib/nova b/lib/nova
index 21157dc400..a43c091822 100644
--- a/lib/nova
+++ b/lib/nova
@@ -414,7 +414,7 @@ function create_nova_conf() {
         add_nova_opt "logging_exception_prefix=%(color)s%(asctime)s.%(msecs)d TRACE %(name)s %(instance)s"
     else
         # Show user_name and project_name instead of user_id and project_id
-        add_nova_opt "logging_context_format_string=%(asctime)s.%(msecs) %(levelname)s %(name)s [%(request_id)s %(user_name)s %(project_name)s] %(instance)s%(message)s"
+        add_nova_opt "logging_context_format_string=%(asctime)s.%(msecs)d %(levelname)s %(name)s [%(request_id)s %(user_name)s %(project_name)s] %(instance)s%(message)s"
     fi
     if is_service_enabled ceilometer; then
         add_nova_opt "instance_usage_audit=True"