Method providing server affinity and client stickiness in a server load balancing device without tcp termination and without keeping flow states

Abstract

A method of routing data from a client through one or more load-balancing routers to a selected load-balanced server among a plurality of servers in a network involves: receiving, at a load balancing node in a path from the client to the plurality of servers, a first packet of a request from a client; creating and storing a mapping of flow identifying information, associated with the first packet, to a client stickiness identifier; pushing the client stickiness label into a sending path list that is stored in association with the first packet; storing the client stickiness label in a mapping of client stickiness labels to server identifiers at a last load balancing node associated with the plurality of servers, wherein the mapping associates the client stickiness label with a server identifier that uniquely identifies a selected server that has been selected from among the plurality of servers to receive the client request; and forwarding all subsequent packets associated with the client request to the same selected server based on looking up the client stickiness label of such subsequent packets in the mapping. As a result, packet flows are rapidly routed from the same client to the same server without time-consuming hop-by-hop routing decisions or repeated load-balancing decisions.