Configure a service in a CISCO ACE load balancer

Hello We are looking for a professional to configure a service in a CISCO ACE load balancer, the current configuration consists of two serverfarm. - The first farm contains four services - The second contains a service - Use regular expression L7 service is routed to the second farm that has only one service, otherwise goes to the first farm. What we want is to set a rule that allows the requirements to transfer some of the first farm server in case it is not the second farm service (by service disruptions or server), following the routing of regular expressions. In this way the configuration is more robust to withstand an eventual fall of the only service available in the second farm.