Abstract: A method is disclosed to set the speed of a network. The method supplies a network interconnected with a system controller and a plurality of switch domains, where each of those plurality of switch domains comprises one or more information storage devices and a switch domain controller, and sets by each of the plurality of switch domains a signaling rate for that switch domain. The method queries in-band by the system controller each of the plurality of switch domains for that switch domain's signaling rate, and provides in-band by each of the plurality of switch domains the signaling rate for that switch domain. The method provides in-band by the system controller to each of the plurality of switch domains a first speed selection command specifying a first network speed, and resets by each of the plurality of switch domains the signaling rate for that switch domain to the first network speed.

Abstract: A method is disclosed to reconfigure a storage array. The method supplies a data storage and retrieval system comprising (N) data storage device assemblies, wherein each of those (N) data storage device assemblies comprises (M) data storage devices, wherein (N) is greater than or equal to 2, and wherein (M) is greater than or equal to 2. The method configures those (N) data storage device assemblies to comprise a spare data storage device assembly and a first storage array comprising the remaining (N?1) data storage device assemblies. In the event Applicants' method detects a failed data storage device disposed in the first storage array, then the method forms a second storage array comprising the first storage array, except the failed data storage device, in combination with a data storage device disposed in the spare data storage device assembly.

Abstract: A method of destage management of redundant data copies in a cache storage subsystem includes providing a plurality of target storage devices, each of the plurality of target storage devices capable of storing a complete copy of a data image. The data image and the plurality of target storage devices are subdivided into a plurality of sub-regions, each of the plurality of sub-regions organized such that a minimum cumulative total of the plurality of sub-regions on the target storage devices equals a number of sub-regions required to form the complete copy of the data image. Data is destaged from a write cache to the plurality of sub-regions on the target storage devices in an order such that a minimum number of sub-regions can be combined to restore the complete copy of the data image.

Abstract: A computer-implemented method replaces a redundant array of independent disks (RAID) array member storage device configured in high density packaging. The high density packaging includes a plurality of field-replaceable units (FRUs). Each FRU has an associated plurality of storage devices. A first spare storage device of a first FRU is captured. The first FRU is dedicated as a plurality of spare storage devices by a RAID controller. A small computer system interface (SCSI) enclosure services (SES) processor (SESP) is initialized to read data from the RAID array member storage device and transfer the data to the first spare storage device. The first spare storage device and the RAID array member storage device are co-resident within a serial attached small computer system interface (SAS) expander local port domain.

Abstract: A method to assign addresses to a plurality of data storage devices, by providing a switch and (N) data storage devices, where each of those (N) data storage devices is interconnected with said switch. The method further establishes (M) arbitrated loop physical addresses (“AL_PAs”), where (M) is less than (N), and assigns a different one of each of the (M) AL_PAs to a different one of the (N) data storage devices, such that the (N) data storage devices comprise (M) AL_PA-assigned data storage devices and (P) non-address-assigned data storage devices. The method then detects a failure of an (i)th AL_PA-assigned data storage device, and transfers the (i)th AL_PA from the failed address-assigned data storage device to a (j)th data storage device, where that (j)th data storage device comprises one of the (P) previously non-addressed data storage devices.

Abstract: A method is disclosed to selectively provide power to a component disposed in an information storage and retrieval system, where the method supplies a controller comprising a control portion in combination with a plurality of components comprising one or more host adapters, one or more device adapter ports, and a Fibre Channel switch. The method monitors the performance of each of those components. The method discontinues the supply of power to first component while continuing to provide power to the remaining plurality of components. The method then resumes providing power to the first component while continuing the supply of power to the remaining plurality of components.

Abstract: A configuration of an array of storage devices compliant with a fibre-channel arbitrated loop (FC-AL) specification includes first and second controllers having integrated first and second SCSI enclosure services (SES) processing devices acting as leader processors. Third and fourth controllers are coupled to the first and second controllers and act as subordinate processors. The third and fourth controllers have integrated third and fourth SCSI enclosure services (SES) processing devices. Each of the SES processing devices synchronizes and merges data to create a single control image for the entire configuration, presenting a single SES instance to a storage device interconnect network and to host controller software.

Abstract: A method of providing a power failure warning in a storage system includes partitioning early power off warning (EPOW) control logic of a storage enclosure to be symmetric with a power distribution network power domain. A power failure warning system for a storage system having a plurality of storage enclosures includes a power system control module coupled to a power supply for control and management of input power to the storage system. An output stage of the power supply is dedicated to a first virtual storage enclosure within one of the plurality of storage enclosures.

Abstract: A method is disclosed to assign network addresses in a storage array disposed in a data storage and retrieval system comprising (P) data storage devices disposed in (N) data storage device assemblies. The method configures the (N) data storage device assemblies to comprise a spare data storage device assembly and a first storage array comprising (N?1) active data storage device assemblies, wherein each data storage device configured in the first storage array is assigned a network address, and wherein one of the spare data storage device disposed in the spare data storage device assembly is assigned a network address. In the event the method detects a failed data storage device disposed in the first storage array, then the method forms a second storage array comprising the first storage array, except the failed data storage device, in combination with the (i)th spare data storage device.

Abstract: An apparatus is disclosed to convert data from a first sector format to a second sector format. The sector format conversion device includes a processor, and microcode which causes the processor to overlay (N) first sectors having a first sector format onto (M) second sectors having a second sector format, where that sector format conversion device does not include an operating system comprising a user mode and a kernel mode.

Abstract: A method of dynamic allocation of non-volatile memory in a cache storage subsystem includes constraining a redundant array of independent disks (RAID) 6 array in an unavailable state, the RAID 6 array having been newly created in the subsystem, destaging data from a write cache to a storage medium to free memory space, reserving the freed memory space for allocation to data-persistent storage, allocating the memory space to an adapter in the subsystem as a target for data in the event of a power loss, and changing the RAID 6 array to an available state. A system for dynamic allocation of non-volatile memory in a cache storage subsystem includes a computer processing device which constrains a newly-created redundant array of independent disks (RAID) 6 array in an unavailable state to execute a reconfiguration method.

Abstract: A system migrates data between a source device and a target device in a storage system. A processor is operational within a local domain of the storage system. A redundant array of independent disks (RAID) controller electrically connected to the processor. The RAID controller divides a capacity of the source device into a plurality of sub-regions, locks the sub-regions from storage activity, establishes a mirroring relationship for write data updates between the source device and target device, and assigns the processor to copy data from the source device to the target device. A method of migrating data includes dividing a capacity of a source device into a plurality of sub-regions, locking the sub-regions from storage activity, establishing a mirroring relationship for write data updates between the source device and a target device, and assigning a local processor to copy data from the source device to the target device.

Abstract: A method provides for dynamic data logging in a storage subsystem. The method determines if a plurality of storage devices has been assigned as a plurality of hot spare devices in the storage subsystem. If the plurality of hot spare devices are assigned, the method determines from the plurality of hot spare devices whether a plurality of storage types with a maximum number of spare devices is present. If a plurality of storage types is present, the method selects a hot spare device from a storage type having the smallest capacity to assign as a logging device, otherwise, the method calculates a plurality of ratios of a first number of storage devices of a shared storage type to a second number of storage devices to which the first number of storage devices can act for as hot spare devices, selecting a storage device with the lowest ratio as the logging device.

Abstract: A storage array disposed in a data storage system is reconfigured. A data storage system is supplied comprising a plurality of data storage devices, wherein each of the plurality of data storage devices is assigned to one of a plurality of data storage arrays, or is assigned as a spare device. An unassigned data storage device is detected. If any of the plurality of data storage arrays comprises an intermixed data storage array, the storage array is reconfigured to restore the intermixed data storage array to a homogeneous technology class comprising the unassigned device. If any of the plurality of data storage arrays comprises a degraded data storage array, the storage array is reconfigured to restore the degraded storage array to optimal reliability, optimal performance, and optimal efficiency.

Abstract: Data storage systems and methods and computer program product for managing data storage systems are provided. The system includes at least first and second storage enclosures, each having a plurality of hard disks configured as first and second arrays of disks and an intra-enclosure path between the first and second arrays. The intra-enclosure path is disabled during normal operation of the storage system. Inter-enclosure paths respectively link the first arrays in the first and second storage enclosures and the second arrays in the first and second storage enclosures and are enabled during normal operation of the storage system.

Abstract: A method for generating an optimal number of spare devices within a RAID storage system having multiple storage device technology classes is disclosed. Each hard drive within the RAID storage system is assigned to a respective spare coverage group according to its attributes. From each of the spare coverage groups, at least one hard drive having a predetermined characteristics is selected as a spare device. A determination is then made as to whether or not an assigned spare device in one of the spare coverage groups is eligible to act as a spare device for another one of the spare coverage groups. In response to a determination that the assigned spare device in one of the spare coverage groups is also eligible to act as a spare device for another one of the spare coverage groups, a hard drive previously selected as a spare device for the other spare coverage group is removed as spare device.

Abstract: A method is disclosed to assign addresses to a plurality of data storage devices. The method provides a switch and (N) data storage devices, where each of those (N) data storage devices is interconnected with said switch. The method further establishes (M) device addresses, where (M) is less than (N), and assigns a different one of each of the (M) device addresses to a different one of the (N) data storage devices, such that the (N) data storage devices comprise (M) address-assigned data storage devices and (P) non-address-assigned data storage devices. The method then detects a failure of the (i)th address-assigned data storage device, and transfers the (i)th address from the failed address-assigned data storage device to the (j)th data storage device, where that (j)th data storage device comprises one of the (P) previously non-addressed data storage devices.

Abstract: A high density storage enclosure houses first and second pluralities of hard disk drives (HDDs). The enclosure may be partitioned into a plurality of virtual enclosures, the first plurality of HDDs being associated with a first virtual enclosure and the second plurality of HDDs being associated with a second virtual enclosure. In the event of a failure within one of the virtual enclosures, an SES in the failed virtual enclosure is isolated from the rest of the virtual enclosure. Then, an inter-enclosure link may be enabled between the failed virtual enclosure and another virtual enclosure. The isolated SES processor may then be accessed to obtain data associated with the failure and to execute commands associated with a recovery process.

Abstract: A high density storage enclosure houses first and second pluralities of hard disk drives (HDDs). The enclosure may be partitioned into a plurality of virtual enclosures, the first plurality of HDDs being associated with a first virtual enclosure and the second plurality of HDDs being associated with a second virtual enclosure. Configuration of the storage enclosure is performed by an SES processor in the storage enclosure accessing configuration parameters received from an external configuration unit coupled to the storage enclosure. The virtual enclosures may be configured as two (or more) independent virtual enclosures on two (or more) independent fabric loops. Power supplies and cooling blowers in the storage enclosure may also be partitioned and assigned to be managed by SES processors in the virtual enclosures.

Abstract: A high density storage enclosure houses first and second pluralities of hard disk drives (HDDs). The enclosure may be partitioned into a plurality of virtual enclosures, the first plurality of HDDs being associated with a first virtual enclosure and the second plurality of HDDs being associated with a second virtual enclosure. Configuration of the storage enclosure is performed by an SES processor in the storage enclosure accessing configuration parameters received from an external configuration unit coupled to the storage enclosure. The virtual enclosures may be configured as two (or more) independent virtual enclosures on two (or more) independent fabrics or may be configured in a trunked manner. Power supplies and cooling blowers in the storage enclosure may also be partitioned and assigned to be managed by SES processors in the virtual enclosures.