Abstract: A method and apparatus for controlling data flow between a computer (10) producing a high speed data stream coupled to a buffered storage device including a disc array (43) and to a group of slower speed storage devices including tape drives arranged in a predetermined logical configuration including arrays (42). The system includes controllers (41) that work together such that if one of the controllers fails, the routing between the controllers and the tape drives is switched to the properly functioning controller without the need to involve the computer or operator in the rerouting process thus providing a redundancy of access control and sequencing. The apparatus also includes components which permit a functioning controller to assume control of tape arrays formerly primarily controlled by the failed controller. In addition, the apparatus provides error check and correction generation devices (45, 58) as well as tape storage device configuration circuitry.