Replicas: Before any write is acknowledged to the host, it is synchronously replicated to one or two designated partner nodes. This means that with 2N one instance of data that is written is stored on the local node and another instance of that data is stored on the designated partner node in the cluster. With 3N one instance of data that is written is stored on the local node, and two other instances of that data are stored on designated partner nodes in the cluster.