An apparatus and associated methodology providing a data storage system operably transferring data between a storage space and a remote device via a network. The data storage system includes a first storage controller having top-level control of a first data storage device and a second storage controller having top-level control of a second data storage device that is different than the first data storage device, the first and second data storage devices forming portions of the storage space. Data pathway logic resides in the first storage controller that performs a direct memory access (DMA) transfer to the second data storage device at a DMA data transfer rate in response to the first storage controller receiving, from the external device via the network, an access request for the second data storage device.