Method and apparatus for transparent server failover for highly available objects

摘要

One embodiment of the present invention provides a method and an apparatus that facilitates transparent failovers from a primary copy (206) of an object on a first server (212) to a secondary copy (216) of the object on a second server (213) when the first server fails, or otherwise becomes unresponsive. The method includes detecting the failure of the first server; selecting the second server; and reconfiguring the second server to act as a new primary server for the object. Additionally, the method includes transparently retrying uncompleted invocations to the object to the second server, without requiring explicit retry commands from a client application program. A variation on this embodiment further includes winding up active invocations to the object before reconfiguring the second server to act as the new primary server. This winding up process may include causing invocations to unresponsive nodes to unblock and complete. Another variation includes blocking new invocations to the object after detecting the failure of the first server, and unblocking these new invocations after reconfiguring the second server to act as the new primary server. Hence, the present invention can greatly simplify programming of client application programs for highly available systems. It also makes it possible to use a client application program written for a non-highly available system in a highly available system.