Digital Equipment Corporation

Hewlett-packard Development Company, L.p.

Emc Corporation

Dennis Mazur

William F Bruckert

Thomas D Bissett

John Munzer

Steven D Sardella

Glenn A Dearth

Mickey Steven Felton

Thomas N Dibb

David E Kovalcin

Bradley Gordon Culter

Bernard Warnakulasooriya

David T Mayo

David Golden

Carlos Alonso

Richard Edward Bracken

Frank Bernaby

Jay H Bhatia

Peter R Mott, Jr

Ann Katan

Communications settings are managed. System characteristics are determined that affect communications on a high speed transmission link between nodes. The system characteristics includes system hardware information and physical characteristics of a cable. Tuning information is derived from the system characteristics. At least some of the tuning information is communicated between the nodes.

Managing communications settings

Embodiments include writing a first data value to a validation variable through a fixed programming interface, where the validation variable includes multiple fields that correspond to multiple fields within a persistent variable. Contents of the validation variable are subsequently read through the fixed programming interface. When the validation variable contents include one or more differences from the first data value, one or more errors are identified.

Variable writing through a fixed programming interface

The invention is a control system using microprocessors which communicate through a Local Area Network (private LAN) to control operation of both processors and input and output subsystems (IO system) of a multiprocessor computer system. The processors each have memory associated therewith, and each processor has an IO system comprising a plurality of busses such as PCI busses, associated therewith. The processors are cabled together in a mesh arrangement so that messages can be transferred between any of the processors and delivered to memory associated with the destination processor, or delivered to an IO system associated with the destination processor, etc. The microprocessors are powered on when power is applied to the chassis of the multiprocessor system, and the microprocessors then control the processors of the multiprocessor system, including applying power to the processors, forming hard partitions containing selected processors, computing routes from a processor to a memory associated with any processor for read and write transactions, computing routes to IO subsystems associated with any processor of the hard partition, forming partition boundaries so that processors in one hard partition cannot read and write to memory or IO systems associated with processors in another hard partition, forming soft partitions of processors, controlling boot-up of operating systems executing on the processors of the multiprocessor computer system, removing power from a failed processor, providing power to a repaired processor, etc.

Partition formation using microprocessors in a multiprocessor computer system

A dual processor computer system includes a first processing system having a central processing unit which executes a series of data processing instructions, a data bus system for transferring data to and from the first central processing unit, a memory unit coupled to the first central processing unit, and a cross-link communications element for transferring data into and out of the first processing system. A similarly configured second processing system, operating independently of the first processing system, is also provided. The cross-link communications element associated with the second processing system is coupled to the cross-link communication element of the first processing system, for transferring data into the second processing system from the first processing system and for transferring data into the first processing system from the second computer system.

Fault tolerant, synchronized twin computer system with error checking of

A fault tolerant computer system has a central processing system which includes at least one set of data pathways, and executes a series of data processing instructions including the transfer of messages along the plurality of data pathways. At least one set of transaction data storage devices are coupled to the data pathways for storing a predetermined number of successive messages transferred most recently on the data pathways. Error checking devices are included for detecting the presence of errors in the central processing system. Error storage devices are coupled to the transaction data storage devices and the error checking devices for causing the transaction data storage devices to cease storing additional messages in response to the detection of errors by the error checking device.

Fault tolerant computer systems with fault isolation and repair

Method and apparatus for controlling initiating of bootstrap loading in a computer system having first and second discrete computing zones is disclosed. Each computing zone includes a status register for storing an operating system run (OSR) bit indicating that the zone has initiated bootstrap loading. A cable connects the computing zones to allow the first and second zones to read the status registers in the second and first zones, respectively. A CPU in each zone only enables initiation of bootstrap loading if the OSR bit in the other zone is not set.

Method and apparatus for controlling initiation of bootstrap loading of

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Worcester, MA, United States of America

Dennis Mazur