1. A method of configuring a load balancing program in a load balancer for a cluster of servers to dispatch client requests to the servers in the cluster, the method comprising the steps of: the load balancer detecting that the cluster cannot handle the client requests with a predetermined level of performance, and in response, the load balancer automatically requesting configuration information for an other server that is not currently active in the cluster, to configure the load balancing program for adding the other server to the cluster to handle client requests; and after receipt of the configuration information for the other server, the load balancer automatically configuring the load balancing program for the cluster to add the other server to the cluster in accordance with the configuration information received for the other server, wherein the configuration information comprises a cookie affinity rule for sending different requests in a given session to a same server clone in a server group, subject to session affinity cookies being unique to each server in the server group, and wherein the load balancer configures the load balancing program for the other server based on the cookie affinity rule.