A fibre channel storage area network (SAN) provides virtualized storage space for a number of servers to a number of virtual disks implemented on various virtual redundant array of inexpensive disks (RAID) devices striped across a plurality of physical disk drives. The SAN includes plural controllers and communication paths to allow for fail-safe and fail-over operation. The plural controllers can be loosely-coupled to provide n-way redundancy and have more than one independent channel for communicating with one another. In the event of a failure involving a controller or controller interface, the virtual disks that are accessed via the affected interfaces are re-mapped to another interface in order to continue to provide high data availability. In particular, a common memory storage device is connected to the back-ends of every controller to provide a storage area. In this manner, the common memory storage device can be accessed via operations similar to those a controller already uses to presently access the physical disks which are connected to the back-end of the controllers.