Autonomic power loss recovery for a multi-cluster storage sub-system

An improved storage controller and method for storing and recovering data are disclosed. The storage controller includes a first cluster for directing data from a host computer to a storage device and a second cluster for directing data from a host computer to a storage device. A first cache memory is connected to the first cluster and a second cache memory is connected to the second cluster. A first preserved area of memory is connected to the first cluster and a second preserved area of memory is connected to the second cluster. Data is directed to the first cache and backed up to the second preserved area in a normal operating mode. Similarly, data is directed to the second cache and backed up to the first preserved area in the normal operating mode. In the event of a power failure or comparable event, data from the first and second preserved areas are transferred to, and stored on, a first storage device. Additionally, data from the first and second preserved areas are transferred to, and stored on, a second storage device. Thus, upon resumption of normal operation, if one of the clusters subsequently fails to resume normal operations, data from the failed cluster is available through the operating cluster.