Hewlett-Packard Development Company, L.p.

Marcelo Moraes De Azevedo

Robert L Jardine

Roger Warren Cox

David L Bernick

Peter H Lipman

Sachin U Naik

Man-Ho Lawrence Lee

Cynthia Sakaguchi

Farangis Aberg

Kousik Bera

Richard J McLaughlin

Techniques for routing data packets in a networked system. Specifically, a network system and methods of arbitrating data packets in a network system are provided. Switching devices are configured to receive one or more data packets, wherein each of the one or more data packets includes a respective source identification. The source identifications are compared to a source identification history mechanism, and the routing order of the data packets is determined based on the comparison.

Method and apparatus for arbitrating data packets in a network system

Each processor in a distributed multi-processor environment maintains a set of connectivity condition scores. The connectivity condition scores are then passed to a pruning process with tie-breaker logic that selects certain of the processors to include in the new system configuration. The surviving processors are selected based on primary connectivity information and secondary processor connectivity condition scores. The result of the pruning/tie-breaker process is transmitted to all of the surviving processors, which continue to maintain connectivity information that can be used in the next regroup incident.

Systems and methods for fault-tolerant processing with processor regrouping based on connectivity conditions

A method of interconnecting a new node into a cluster of other nodes. The new node broadcasts a configuration (DP) packet describing itself to the other nodes of the cluster. The other nodes then respond by setting up communications information enabling the new node to directly communicate with a monitor process in the responding nodes and sending that information (DI packet) to the new node. The new node then sets up information enabling the responding nodes to communicate with a monitor process on the new node and sends that information (DC packet) to the responding nodes. The responding nodes then acknowledge the information (DA packet) and the new node is then interconnected with the responding nodes. The DP and DI packets are sent via a permissive interrupt mechanism, received by each processor unit making up a node and forwarded to the monitor process of the node.

Method and apparatus for discovering computer systems in a distributed multi-system cluster

Maintenance of a network resource is regulated by providing a lock data area that indicates an ownership status of the network resource, and a lock server process to maintain the lock data area. A client that is to perform maintenance on the network resource sends a command to the lock server process to modify the lock data area to indicate ownership of the network resource by the particular client. In response, the lock server process sends a response indicating whether or not ownership of the network resource by the client has been established. If ownership is indicated, the client performs the maintenance on the network resource. If ownership is not indicated, the maintenance is not performed. Provision is made for retries, and also for forcing the lock if a current owner becomes moribund.

Networked system for assuring synchronous access to critical facilities

An apparatus and protocol to determine the group of processors that will survive communications faults and/or timed-event failures in a distributed multiprocessor or clustered system. The processors are coupled to one another by an inter-processor communication network that is used, inter alia, by each processor to send path probe messages to each of the other processor units on all available network paths. A processor is suspected of being communicatively isolated, or having ceased operations, when one or more of the other processors detects the absence of an acknowledgment response from the processor. When this happens, all of the processors are subjected to a series of stages in which they repeatedly broadcast their status and connectivity to each other.

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Round Rock, TX, United States of America

Marcelo Moraes De Azevedo