International Business Machines Corporation

Jonathan W L Short

Gordon Douglas Hutchison

Gareth Paul Jones

Daniel S Critchley

Roderick G C Moore

Jonathan Ian Settle

Timothy Finbarr McCarthy

Paul Nicholas Cashman

Raymond Jepson

Tim F McCarthy

Dan Critchley

Denis Senin

Mechanisms are provided for cabling a set of enclosures. Using a set of cables that comprises eight physical layers (PHYs), the set of enclosures are coupled together such that: for a first enclosure and each intermediate enclosure in the set of enclosures, at least four PHYs of the eight PHYs terminate within a Serial Attached Small Computer System Interface (SCSI) (SAS) expander of the first enclosure and a SAS expander of each intermediate enclosure white passing through a remaining four PHYs of the eight PHYs without connecting to the respective SAS expander; and, for a last enclosure in the set of enclosures, all of the eight PHYs terminate in the SAS expander of the last enclosure.

Cabling a set of enclosures

A method and a computer program product for latency measurement in an I/O operation. A storage system measures time periods taken in a write I/O operation and, using the measures time periods in the write I/O operation, the storage system monitors a delay that is caused by at least one of a host and a storage area network. A storage system measures time periods taken in a read I/O operation and, using the measures time periods in the read I/O operation, the storage system monitors a delay that is caused by at least one of a host and a storage area network in the read I/O operation.

Latency measurement in an I/O operation of computer data storage

A RAID system, RAID controller, method, and computer program product for reducing the number of reads of XOR data in a multi-storage-enclosure RAID array includes a RAID array controller that implements a selected distributed RAID scheme. The RAID array controller determines a set of drives and logical block addresses corresponding to a parity group and divides the set of drives into subsets of drives that are located within each individual storage enclosure of the multiple storage enclosures. The controller issues a single EnclosureXOR Read to each storage enclosure corresponding to the subsets of drives to read enclosure-level intermediate XOR data calculated by each storage enclosure for each subset of drives and in response to receiving the enclosure-level intermediate XOR data results from all storage drives in the parity group, and calculates an array level XOR result by XORing the enclosure-level intermediate XOR data results from the storage enclosures.

RAID systems and methods for improved data recovery performance

A RAID system includes a storage enclosure comprising a plurality of independent data storage devices. A processor is associated with the storage enclosure. The processor is configured for processing data for the plurality of storage devices of the storage enclosure. The processor is configured to receive a request to read intermediate XOR data based on data stored in two or more of the plurality of storage devices of the storage enclosure. The processor is further configured to read data from each of the two or more storage devices in response to receiving the request. The processor is configured to determine intermediate XOR data based on the data read from the two or more storage devices of the storage enclosure. The intermediate XOR data may be provided to a RAID storage controller and may be used in an XOR-based recovery process.

An embodiment of the invention may include a method, computer program product and computer system for a cable removal system. The embodiment may include a computing device that determines whether a user is contacting a network cable. The network cable is physical connection between a first device and a second device. The first device includes at least one network port. The embodiment may include a computing device determining whether an information transmission across the network cable can be rerouted based on determining that the user is contacting the network cable. The embodiment may include a computing device rerouting information transmission based on determining that the information transmission across the network cable can be rerouted. The embodiment may include a computing device alerting the user that there is no information transmission across the network cable based on rerouting the information transmission.

Cable removal system

A fault-tolerant storage system includes a first strand comprising a first initiating device connected to a first expansion device of a first set of serially connected expansion devices, a second strand comprising a second initiating device connected to a first expansion device of a second set of serially connected expansion devices, and a plurality of zoning switches that each connect an expansion device in the first set of serially connected expansion devices to a corresponding expansion device in the second set of serially connected expansion devices. A computer program product and method executed by a computer corresponding to the above system are also disclosed herein.

Routing data streams around faults in strands

A method for use in a computerized storage system comprising one or more replaceable units, for managing testing of one or more replacement units, where the storage system is automatically placed in a testing mode in response to a given unit being replaced and if testing fails the storage system automatically fails back to a service mode.

Computerised storage system comprising replaceable units for managing testing of replacement units

A management apparatus operable for protecting data on a failing storage device in a data processing system including a storage array having at least one of a plurality of storage devices. The management apparatus includes a receiver component for receiving a failure message indicating that the plurality of storage devices comprises the failing storage device. An analyzer component is in communication with the receiver component and responsive to receipt of the failure message, for analyzing the failure message. A sender component is in communication with the analyzer component. The sender component is adapted for, in response to the analyzer component determining the failing storage device, sending a zoning message, the zoning message instructing the storage array to isolate the failing storage device, and sending a protect message. The protect message instructs the storage array to protect data on the failing storage device.

Protection of data on failing storage devices

A method implemented in a computer infrastructure having computer executable code having programming instructions tangibly embodied on a computer readable medium. The programming instructions are operable to configure an initiator-to-initiator message route in a switched fiber channel arbitrated loop (FCAL) network such that the initiator-to-initiator message route traverses a replacement field replaceable unit (FRU). Additionally, the programming instructions are operable to transmit a verification initiator-to-initiator message along the initiator-to-initiator message route to verify proper operation of the replacement FRU.

Growing community of inventors

Eastleigh, United Kingdom

Jonathan W L Short