diff --git a/README.rst b/README.rst
index b0a0323..8e539d3 100644
--- a/README.rst
+++ b/README.rst
@@ -167,6 +167,7 @@
         ...
         tokens:
           engine: fernet
+          max_active_keys: 3
         ...
 
 Keystone domain with LDAP backend, using SQL for role/project assignment