Red Cluster brings together a set of redis servers and allows you to read and write to them as though you were writing to just one. A few of the reasons you might want to consider clustering could be: * Robustness - Having a write master and read slaves * Harnessing the multiple cores you have running while not compromising on the speed of redis * Fault tolerance - When one of the masters goes down a slave in the replica sets gets promoted \ automatically, with no down-time