Patent ID: 7543066

Claim:
A method of maintaining session affinity in a server farm coupled to receive client requests, said server farm comprising multiple server groups, each server group comprising multiple clone servers, said method comprising the steps of: (1) associating a collection of related client requests with a unique session identification code; (2) responsive to receipt of a client request, determining to which of said server groups said client request can be dispatched; (3) associating with said collection of requests sharing a session identification code a list of every server in said server farm that has serviced a request in said collection; (4) responsive to said receipt of a client request which comprises a session identification code, determining if said list associated with said received session identification code includes a server identification code that matches a server identification code of a server in said determined server group; and (5) if a match is detected, dispatching said client request to said matched server; wherein steps (1) and (4) comprise sending said session identification code and said unique server identification code, respectively, to a client machine that issued said request so that said client machine can include said session identification code and said unique server identification code as part of future requests it issues to said server farm.