diff --git a/admin_manual/configuration_server/caching_configuration.rst b/admin_manual/configuration_server/caching_configuration.rst
index 9bf1b5a7e..0649e7cfb 100644
--- a/admin_manual/configuration_server/caching_configuration.rst
+++ b/admin_manual/configuration_server/caching_configuration.rst
@@ -205,6 +205,9 @@ The following options are available to configure when using a redis cluster (all
       'password'        => 'password',
       'dbindex'         => 0,
    ]
+   
+      
+.. note:: The port is required as part of the server URL. However, it is not necesarry to list all servers: for example, if all servers are load balanced via the same DNS name, only that server name is required.
 
 Connecting to single Redis server over TCP
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^