Abstract: A configurable storage array includes a backplane, a plurality of storage devices coupled to the backplane, a segmentable bus coupled to the storage devices, a plurality of input/output connectors coupled to the segmentable bus, and a control board. The control board includes control logic adapted to determine an arrangement of connectors coupled to the input/output connectors and configure the segmentable bus to define a plurality of storage device arrays based on the arrangement. A method for configuring a storage array having a plurality of storage devices includes determining an arrangement of connectors coupled to input/output connectors of the configuring a storage array; and grouping subsets of the storage devices onto isolated bus segments in the storage array based on the arrangement of connectors.

Abstract: A primary server/standby server network configuration according to the invention includes a primary server executing network operating system software and a standby server monitoring for the proper operation of the primary server, where both the primary server and the standby server are connected to a storage system. If the primary server fails, the standby server instructs the storage system to switch its hardware connections to the standby server, allowing the standby server to boot the operating system. This instruction is done via in-band signaling. Further, multiple primary servers can be backed up by a single standby server.

Abstract: SCSI controller circuitry for controlling devices on a wide SCSI bus that implement the wide SCSI bus standard according to SCSI-2 is implemented with improved circuitry for providing the wide SCSI bus acknowledge signal ACKB*. Specifically, a high speed analog buffer chip is provided that can sync and source over 55 milliamps, that has a propagation delay of 1.5 nanoseconds, and that follows its input with a high degree of accuracy. Using this circuitry, glitches are eliminated in devices with high lump capacitive loads and cross-talk on the wide SCSI bus.

Abstract: A primary server/standby server network configuration according to the invention includes a primary server executing network operating system software and a standby server monitoring for the proper operation of the primary server, where both the primary server and the standby server are connected to a storage system. If the primary server fails, the standby server instructs the storage system to switch its hardware connections to the standby server, allowing the standby server to boot the operating system. This instruction is done via in-band signaling. Further, multiple primary servers can be backed up by a single standby server.

Abstract: A disk array controller includes a local microprocessor, a bus master interface, a compatible interface, buffer memory and a disk interface. The controller includes a DMA controller between the microprocessor, the bus master interface, the compatibility interface and the buffer memory. DMA controllers are also provided between the disk interface and the buffer memory. One of these DMA channels includes an XOR engine used to develop parity information used with the disk array. The various DMA controllers are cycled to allow access to the buffer memory and the disk interface. A posted write memory system is connected as a selectable disk drive to the disk interface. The posted write memory system includes mirrored, parity checked and battery backed semiconductor memory to allow posted write data to be retained during power down conditions with only a very small change of data loss.

Abstract: A series of hard disk drives are secured atop molded plastic support trays slidably and removably received in opposing guide channel member pairs snap-fitted into opposite side walls of a sheet metal cage structure externally used in conjunction with a file server or other computer device. Snap-fitted into rear end portions of the trays are small printed circuit boards that are insertable into hot plug sockets at the rear of the cage. Forwardly projecting guard plates on the rear end of the cage block manual access to the board/socket interface, and the surface mounted grounding leads on the board extend rearwardly beyond its signal leads to enhance grounding safety during disk drive installation and removal. At the front end of each tray is a vertical support plate upon which LED indicating lights are conveniently mounted for the associated disk drive.