A massively scalable architecture for providing a self-monitoring and self-correcting storage system that is capable of handling hundreds of millions of users and tens of billions of files. The system includes one or more clusters storing data elements that are received from a plurality of clients. Each cluster comprises a plurality of storage servers. The storage system facilitates the addition of new storage servers, and the fast recovery of failed storage servers, by logging system transactions in multiple journals of different lengths. When a storage server fails, a cluster backup determines the time of failure and replays one of the journals in order to bring the failed storage server up to date.