Scripts to update a MongoDB cluster to a different version.
The intent here is to provide a set of scripts that can perform a rolling update of a mongodb cluster. The way that this is achieved is by delivering to each MongoDB node a script that will idenitfy that node's role, then query the cluster to determine when is the right time to update the binaries and restart any MongoDB processes, based on that node's role in the cluster. Script execution will be cron-determined with separate phases for config servers, secondaries/arbiters, primaries and finally mongoses. The delivery mechanism at this time is puppet for which a puppet class is provided. The goal is to upgrade a cluster with no down time - regardless of the number of nodes - within 1 hour.