Patent attributes
A system and method for facilitating an automatic rolling upgrade of distributed software. In a set of computing devices (e.g., a cluster), each node executes the distributed program, but different nodes may operate any number of different versions of the program. During a rolling upgrade of the software, the nodes all operate according to a specified acting version of the software. A node attempting the join the cluster may be required to have a software version at least equal to the acting version. When all nodes have been upgraded to a version newer than the current acting version, the acting version is reset to the lowest software version installed on a node. The rolling upgrade completes automatically when all nodes run at a specified software version (e.g., the most recent) or have the same version installed.
