Abstract: A system and method enables a file server, to support multi path input/output operations for Fibre Channel devices. Upon each Fibre Channel Arbitrated Loop initialization event generated, the system and method updates a path and device instance to track multiple paths to a given device. While the file server is attempting input/output operations, the failure of a given path can be corrected by the use of another path associated with a given device. The data structures generated by the low levels of the storage operating system are exposed for use by upper level services for routing a storage device identification purposes.

Abstract: A system and method enables a file server, to support multi path input/output operations for Fibre Channel devices. Upon each Fibre Channel Arbitrated Loop initialization event generated, the system and method updates a path and device instance to track multiple paths to a given device. While the file server is attempting input/output operations, the failure of a given path can be corrected by the use of another path associated with a given device. The data structures generated by the low levels of the storage operating system are exposed for use by upper level services for routing a storage device identification purposes.

Abstract: A computer server system and a method for operating the system are described. An address and a status of each computer device of a plurality of computer devices accessible to a switch is written into a memory in the switch. The status of a first computer device which is off line is set to indicate that the first computer device is off line. The status information is read from the memory in the switch by a second computer device so that the second computer device knows that the first computer device is off line. Embodiments are described where the status of a data storage device and the status of a server are written to the memory in the switch.

Abstract: A system and method of storing data for use by storage operating systems in memories associated with switch ports. The data is written to a switch port memory, which is readable by all devices connected to the switch, and by all devices connected to a switching fabric containing that switch. When a device connected to the switching fabric requires the information, the device retrieves the stored information from the switch-port memory, without the need for any interaction of the device that originally wrote the data.

Abstract: The present invention provides a novel coordinated shared storage architecture that permits the amortization of cost of the spares over any number of the storage systems and enables improvements to a number of storage system operations. The coordinated shared storage architecture comprises a plurality of storage systems disk shelves via a plurality of intermediate network devices, such as hubs. Each storage system includes a storage operating system having a target device driver module. The target device driver module permits the storage system to function as a SCSI target and thereby receive and process commands directed to it from other storage systems.

Abstract: The invention provides a method and system for routing or switching file system requests in a mass storage system. The mass storage system includes multiple storage devices coupled using fiber channel to a routing or switching device disposed internally within each shelf of mass storage devices in the mass storage system, and coupled directly to each individual mass storage device in that shelf. The switching device receives requests, identifies an individual target storage device for each such request, and sends each such request to its designated target storage device. The switching device also receives responses to such requests from each individual storage device within the shelf, and sends those responses from the storage device to an external medium with which the response can be delivered to the original requester.

Abstract: A system and method for disk ownership in a network storage system. Each disk has two ownership attributes set to show that a particular file server owns the disk. In a preferred embodiment the first ownership attribute is the serial number of the file server being written to a specific location on each disk and the second ownership attribute is setting a SCSI-3 persistent reservation. In a system utilizing this disk ownership method, multiple file servers can read data from a given disk, but only the file server that owns a particular disk can write data to the disk.

Abstract: A modular and highly available RAID system has a fiber channel arbitrated loop (FC-AL) interface coupled with a disk array. Fault-tolerant operation is assured. The system provides dual and isolated arbitrated host and storage device loop circuits for redundant, independent input/output (I/O) paths to local and/or remote host computers. Each loop includes bypass circuits which prevent the failure of any device (host computer or storage device) from affecting the operation of loop. Orthogonal data striping may be used to further assure data integrity.