Abstract:
A storage subsystem and a storage controller adapted to take advantage of high data transfer rates of fiber channels while offering enhanced reliability and availability and capable of connecting with a plurality of host computers having multiple different interfaces. A loop is provided to serve as a common loop channel having fiber channel interfaces. Host interface controllers (HIFC) connected to host computers having different interfaces permit conversion between the fiber channel interface and a different interface as needed. Control processors, shared by the host interface controllers, each reference FCAL (fiber channel arbitrated loop) management information to capture a frame having an address of the processor in question from among the frames passing through the loop. I/O processing is then carried out by the controller in accordance with a range of logical unit numbers (LUN) set in the captured frame.
Abstract:
Aspects of the present invention allow the implementation of one or more data pools using portions or sectors of one or more hard disk drives. Aspects of the invention incorporate at least a method and system of implementing the one or more data pools. The method of implementing a data pool using one or more data storage drives may comprise first generating a first partition table and a second partition table, wherein the first partition table is a mirror image of said second partition table. The method further comprises second generating a first pool information block and a second pool information block, wherein the first pool information block is a mirror image of said second pool information block. The system of implementing a data pool using one or more data storage drives may comprise a memory, a software resident in the memory, and a processor capable of executing the software.
Abstract:
A data storage system is provided with a pair of controllers and circuitry configured for failing back from a single active write back mode to a dual active write back mode by copying cached data directly from a cache of a survivor controller of the pair of controllers to a cache of the other controller. A method is provided for failing over from a dual active mode of first and second controllers to a single active mode of the first controller by relying on previously mirrored cache data by the second controller; reinitializing the second controller; and failing back to the dual active mode by copying cached data directly from the first controller to the second controller.
Abstract:
A storage subsystem and a storage controller adapted to take advantage of high data transfer rates of fibre channels while offering enhanced reliability and availability and capable of connecting with a plurality of host computers having multiple different interfaces. A loop is provided to serve as a common loop channel having fibre channel interfaces. Host interface controllers (HIFC) connected to host computers having different interfaces permit conversion between the fibre channel interface and a different interface as needed. Control processors, shared by the host interface controllers, each reference FCAL (fibre channel arbitrated loop) management information to capture a frame having an address of the processor in question from among the frames passing through the loop. I/O processing is then carried out by the controller in accordance with a range of logical unit numbers (LUN) set in the captured frame.
Abstract:
A system interface includes a plurality of first directors, a plurality of second directors, a data transfer section and a message network. The data transfer section includes a cache memory. The cache memory is coupled to the plurality of first and second directors. The messaging network operates independently of the data transfer section and such network is coupled to the plurality of first directors and the plurality of second directors. The first and second directors control data transfer between the first directors and the second directors in response to messages passing between the first directors and the second directors through the messaging network to facilitate data transfer between first directors and the second directors. The data passes through the cache memory in the data transfer section. A method for operating a data storage system adapted to transfer data between a host computer/server and a bank of disk drives. The method includes transferring messages through a messaging network with the data being transferred between the host computer/server and the bank of disk drives through a cache memory, such message network being independent of the cache memory.
Abstract:
Multiple Array Management Functions (AMFs) are connected to multiple redundancy groups over a storage area network (SAN), such as a fiber-channel based SAN. The multiple AMFs share management responsibility of the redundancy groups, each of which typically includes multiple resources spread over multiple disks. The AMFs provide concurrent access to the redundancy groups for associated host systems. When a host requests an AMF to perform an operation on a resource, the AMF synchronizes with the other AMFs sharing control of the redundancy group that includes the resource to be operated on, so as to obtain a lock on the resource. While performing the operation, the AMF send replication data and state information associated with the resource such that if the AMF fails, any of the other AMFs are able to complete the operation and maintain data reliability and coherency.
Abstract:
A method for restarting a process running on a first processor includes preparing a second processor, copying process context information to the second processor, starting a second process using the context information on the second processor, and terminating a first process running on the first processor. The second process performs an equivalent function to the first process.
Abstract:
One aspect is directed to a method and apparatus for transferring information, through a shared storage system, between first and second processes running on first and second computers, respectively. Both computers are coupled to a data storage system, with the first computer being coupled through multiple paths. In accordance with one aspect of the invention, at least one of the multiple paths is selected through which to transfer the information between the first process and the data storage system, so that communication between the first process and the shared storage system is not constrained to any particular path. Another aspect is directed to a method and apparatus for processing an out of band control command executed by a host computer in a multi-path system and targeting a device. A path is selected for transmitting the out of band control command to the device based upon a selection criteria that enables the selected path to be other than a specific target path identified by the out of band control command.
Abstract:
A method and apparatus for dynamically reconfiguring a computing system are disclosed. The method comprises detecting a predetermined condition triggering a reconfiguration of the computing system; and dynamically reconfiguring a signal path affected by the condition from a first mode to a second mode responsive to detecting the condition. The apparatus is a computing system, comprising: a plurality of I/O switches, a crossbar switch, a plurality of signal paths; and a system controller. Each signal path is defined by an I/O switch and the crossbar switch. The system controller is capable of detecting a predetermined condition triggering a reconfiguration and dynamically reconfiguring at least one of the signal paths affected by the condition from a first mode to a second mode.
Abstract:
Multiple Array Management Functions (AMFs) are connected to multiple redundancy groups over a storage area network (SAN), such as a fiber-channel based SAN. The multiple AMFs share management responsibility of the redundancy groups, each of which typically includes multiple resources spread over multiple disks. The AMFs provide concurrent access to the redundancy groups for associated host systems. When a host requests an AMF to perform an operation on a resource, the AMF synchronizes with the other AMFs sharing control of the redundancy group that includes the resource to be operated on, so as to obtain a lock on the resource. While performing the operation, the AMF send replication data and state information associated with the resource such that if the AMF fails, any of the other AMFs are able to complete the operation and maintain data reliability and coherency.