A bi-directional reflective memory channel between a pair of storage
controllers is used to maintain a mirrored copy of each storage
controller's native buffer contents within the buffer of the other
storage controller. To maintain such mirrored copies, buffer write
operations that fall within a reflective memory segment of one storage
controller are automatically reflected across this channel to the other
storage controller for execution, and vice versa. The write operations
are preferably transmitted across the reflective memory channel using a
protocol that provides for error checking, acknowledgements, and
retransmissions. This protocol is preferably implemented entirely in
automated circuitry, so that the mirrored copies are maintained without
any CPU intervention during error-free operation. When a failover occurs,
the surviving storage controller uses the mirrored copy of the failed
storage controller's native buffer contents to assume control over the
failed storage controller's disk drives.