Abstract:
One embodiment of the present invention is an integrated circuit implementing a storage-shelf router, used in combination with path controller cards and optionally with other storage-shelf routers, to interconnect SATA disks within a storage shelf or disk array to a high-bandwidth communications medium, such as an FC arbitrated loop. When two, four, six, or eight or more storage-shelf routers are used within a storage shelf, and the interconnections between the storage-shelf routers, disk drives, and external communications media are properly designed and configured, the resulting storage shelf constitutes a discrete, highly-available component that may be included in a disk array or in other types of electronic devices. The storage-shelf router features a disk-drive adaptation layer that allows a storage-shelf router to interface to, and manage, any of many different types of disk drives. The disk-drive adaptation layer includes a disk-profile table and associated firmware logic.
Abstract:
A method and an apparatus for providing multiple ports (148, 152) to a single port device (140) are provided. According to the present invention, single port devices that are incapable of communicating across a shared communication bus, and therefore require a point to point communication channel, may be interconnected to multiple hosts using a switch assembly (144). The switch assembly selectively establishes a communication path between a single host (104 or 108) and a device (140). Additionally, the present invention provides a method and apparatus by which computer subsystems, such as RAID storage subsystems, may be implemented using inexpensive storage devices. Furthermore, the present invention provides a method and apparatus for providing a high reliability computer system by configuring the subsystem such that no single active component failure will result in the failure of the entire subsystem.
Abstract:
A method, system, and apparatus for accessing a plurality of storage devices in a storage area network (SAN) as network attached storage (NAS) in a data communication network is described. A SAN server includes a first interface and a second interface. The first interface is configured to be coupled to the SAN. The second interface is coupled to a first data communication network. A NAS server includes a third interface and fourth interface. The third interface is configured to be coupled to a second data communication network. The fourth interface is coupled to the first data communication network. The SAN server allocates a first portion of the plurality of storage devices in the SAN to be accessible through the second interface to at least one first host coupled to the first data communication network. The SAN server allocates a second portion of the plurality of storage devices in the SAN to the NAS server. The NAS server configures access to the second portion of the plurality of storage devices to at least one second host coupled to the second data communication network.
Abstract:
A network storage controller (100) for transferring data between a host computer and a storage device, such as a redundant array of inexpensive disks (RAI), is disclosed. The network storage controller (100) includes at least one channel interface module (136, 140) which is adapted to be connected to the host computer and storage device. The channel interface module (136, 140) is connected to a passive backplane (116), and selectively transfers data between the host computer and storage device and the passive backplane (116). The network storage controller (100) also includes at least one controller management module (104, 108), attached to the passive backplane (116). The controller management module (104, 108) communicates with the channel interface module (136, 140) via the passive backplane (116), and processes and temporarily stores data received from the host computer or storage device. In applications where redundancy is required, at least two controller management modules (104, 108) and at least two channel interface modules (136, 140) may be used. The controller management modules (104, 108) may mirror data between one another using the passive backplane (116) and a shared communication path on the channel interface modules (136, 140), thereby substantially avoiding the use of host or disk channels to mirror data. The channel interface modules (136, 140) are operable to connect the host computer or storage device to one or more controller memory modules (104, 108). The controller management modules (104, 108) may include a DMA engine to facilitate the transfer of mirrored data.
Abstract:
A storage provisioning policy is created by specifying storage heuristics for storage attributes using storage heuristic metadata. Storage attributes characterize a storage device and storage heuristic metadata describe how to specify a storage heuristic (S602). Using the storage heuristic metadata, storage heuristics are defined to express a rule or constraint as a function of a storage attribute (S604). In addition, the storage provisioning policy may also specify mapping rules (S606) for exporting the storage to a consumer of the storage, such as the server or server cluster.
Abstract:
A data storage system having a plurality of disk drives. Each one has a pair of ports. A pair of directors controls the flow of data to and from the disk drives. A first and second fibre channel port by-pass selector section are provided. The first fibre channel selector section includes: a input/output port coupled to a first one of the directors; and, a plurality of output/input ports connected between a first one of the ports of the plurality of disk drives through a first plurality of fibre channel links. The first fibre channel port by-pass selector section is adapted to couple the first one of the directors serially to one, or ones, of the first ports of the plurality of disk drives through a first fibre channel selectively in accordance with a control signal fed to the first fibre channel by-pass selector section. The first fibre channel includes one, or more, of the first plurality of fibre channel links. The second fibre channel port by-pass selector section is similarly configured.
Abstract:
A method and apparatus for performing fault-tolerant network computing using redundant communications modules. The apparatus comprises a pair of network appliances coupled to a network. The appliances interact with one another to detect a failure in one appliance and instantly transition operations from the failed appliance to a functional appliance. Each appliance monitors the status of another appliance using multiple, redundant communication channels are formed using a plurality of network interface cards.
Abstract:
A data processing system (20) with a RAID cache disk subsystem utilizes three RAID cache disk controllers (61, 62, 63) to provide increased performance along with increased reliability, especially in the event of a failure of one of the disk controllers. Disk writes are mirrored in two disk controllers in order to guarantee integrity in the event of a disk controller or interface failure. Typically this write caching must be terminated when one of the controllers fails in order to maintain integrity. In the present invention, write caching continues utilizing the two remaining controllers (62, 63).
Abstract:
A data storage system having a first storage channel (14a1), a first controller (10a) coupled to the first storage channel (14a1), a first storage device (16a) coupled to the first storage channel (14a1), a second storage channel (14a2), a second storage device (16b) coupled to the second storage channel (14a2), and a switch (18a) coupled to the first storage channel (14a1) and the second storage channel (14a2). The switch (18a) separates the first storage channel (14a1) from the second storage channel (14a2) in a first state and connects the first storage channel (14a1) and the second storage channel (14a2) in a second state.