Abstract: A clone managed session affinity system, method and apparatus. A clone-managed session affinity method includes receiving a request from a client. The request includes a reference to a selected clone with which the client has a session affinity relationship. The clone determines whether a session affinity cancellation condition has arisen. If the clone determines that a session affinity termination condition has arisen, the session affinity relationship is cancelled.

Abstract: The invention is a method and apparatus for maintaining session affinity within a server farm when requests sharing a session ID switch between server groups or between server clones in a single server group. In accordance with the invention, client requests include a list of clone identification codes, each code uniquely identifying a clone within a server group for handling the request. The clone identification code may be appended to a session identification code. For each different server that handles a request in a session, a new clone identification code is appended without deleting or overwriting any previously appended clone identification codes. When a request is received, the list of clone identification codes associated with the request is parsed in a predetermined order to search for the first clone identification code that matches one of the clone identification codes of a server in the appropriate server group. If a match is detected, the request is dispatched to that clone.

Abstract: The invention is a method and apparatus for invalidating session data stored in a database. In accordance with the invention, http sessions stored in the database are allowed to remain in the database without real time testing for session time out. Instead, invalid (or timed out) sessions remain in the database until a specified time. At that specified time, all http sessions are invalidated without actually testing them for time out. Alternately, each session can be individually tested for time out and only those sessions which have actually timed out are removed from the database or otherwise invalidated.

Abstract: A clone managed session affinity system, method and apparatus. A clone-managed session affinity method can include receiving a request from a client. The request can include a reference to a selected clone with which the client has a session affinity relationship. The clone can determine whether a session affinity cancellation condition has arisen. If the clone determines that a session affinity termination condition has arisen, the session affinity relationship can be cancelled.

Abstract: The invention is a method and apparatus for maintaining session affinity within a server farm when requests sharing a session ID switch between server groups or between server clones in a single server group. In accordance with the invention, client requests include a list of clone identification codes, each code uniquely identifying a clone within a server group for handling the request. The clone identification code may be appended to a session identification code. For each different server that handles a request in a session, a new clone identification code is appended without deleting or overwriting any previously appended clone identification codes. When a request is received, the list of clone identification codes associated with the request is parsed in a predetermined order to search for the first clone identification code that matches one of the clone identification codes of a server in the appropriate server group. If a match is detected, the request is dispatched to that clone.

Abstract: The invention is a method and apparatus for invalidating session data stored in a database. In accordance with the invention, http sessions stored in the database are allowed to remain in the database without real time testing for session time out. Instead, invalid (or timed out) sessions remain in the database until a specified time. At that specified time, all http sessions are invalidated without actually testing them for time out. Alternately, each session can be individually tested for time out and only those sessions which have actually timed out are removed from the database or otherwise invalidated.

Abstract: The invention and apparatus for updating a back-end database for storing http session for access by multiple servers in a server farm in which the number of writes by the servers to the database are minimized. Particularly, each server maintains up to date copy of the http session data for each http session and writes the http session data to the back-end http session database that is accessible by all of the associated servers only at predetermined intervals. The intervals may be dictated on a purely time basis. Alternately, the interval may be after a specified number of requests are received in a given session or a specified number of changes are made to the http session data of the particular session.