Different versions of the checkpoint/restart function will not coexist on the same cluster of nodes. An application built with earlier checkpoint libraries (such as LoadLeveler 2.2) can only run on nodes running that version of LoadLeveler. For example, an applications built to use LoadLeveler 3.1 checkpointing must be run on nodes running LoadLeveler 3.1. A program which was checkpointed on an earlier version of LoadLeveler cannot be restarted on 3.1, and vice versa.