Patent ID: 8677086

Claim:
A data storage system comprising: a first storage processor including a first memory device; a second storage processor including a secondary memory device; and a third memory device coupled to the first storage processor and the second storage processor wherein the first and second storage processors are interconnected to enable minoring of data from the first memory device to the second memory device and minoring of data from the second memory device to the first memory device and monitoring of an availability of the other of the first storage processor and the second storage processor; wherein the first and second storage processors monitor the availability of the other by transmitting a heartbeat message therebetween; and wherein, during a first mode of operation, data processed by the first storage processor and the second storage processor is mirrored from the first memory device to the second memory device and from the second memory device to the first memory device and, during a second mode of operation, data processed by the first storage processor is mirrored from the first memory device to the third memory device.