Abstract: A remote monitoring diagnostic system and method utilize two different storage techniques. A time-coherent storage technique and change-detect storage technique are utilized to ensure that sensor signals are stored accurately and efficiently. A central diagnostic system can poll or pull the sensor values remotely. Additionally, an on-site monitor can perform anomaly detection to generate malfunction data.

Abstract: A method for use in a peer to peer remote copy (PPRC) system having primary and secondary storage systems to make data available from established PPRC storage volume pairs includes isolating the secondary storage system to be in a stand alone state such that access from any storage systems and hosts is prevented. It is then determined if each storage volume of the secondary storage system is part of an established PPRC storage volume pair. Each established PPRC storage volume pair is then terminated such that the storage volumes of the secondary storage system that are part of the established PPRC storage volume pairs are accessible to hosts. The secondary storage system is then made available to hosts to effect data recovery of the established PPRC storage volumes.

Abstract: A redundant system (20) comprises a first unit (21), a second unit (22), and a synchronization server (24). The first unit (21) and a second unit (22) each include plural state machines (SMs) for performing tasks. At least some of the state machines provided at the first unit simultaneously perform same tasks as at least corresponding ones of some of the state machines provided at the second unit. When a state machine of the second unit needs to be resynchronized, the synchronization server (24) receives a resynchronization request (2-1) from the resync requesting state machine of the second unit and thereupon provides an out-of-synchronization indication (2-2) to a corresponding state machine of the first unit. In response to the out-of-synchronization indication (2-2) from the synchronization server, the corresponding state machine of the first unit generates a resynchronization request (2-3) at an time deemed appropriate by the corresponding state machine.

Abstract: A system and method of monitoring and analyzing the performance of a computer system and its components in a data processing network and for proposing changes to the network to improve the performance. The system involves identifying undesirable conditions (sometimes called bottlenecks) in the system, determining which bottlenecks are the most severe in affecting the performance of the system and in proposing changes to the components of the system to improve performance of the network. The present invention uses historical data and forecasting techniques to predict bottlenecks which have not occurred yet but which can be expected, so that further bottlenecks can be projected, along with a prediction interval to indicate the confidence of the prediction. The further projections and the prediction interval are provided in a graph which is available to the user over the Internet, if desired, using HTML and hot links.

Abstract: The present invention relates to providing processor redundancy in a system such as a router. According to an embodiment of the present invention, in a system having two or more processors, initialization sequence is started. During the initialization sequence, a redundancy subsystem is initialized. The redundancy subsystem identifies the projects or assignments that are to be off loaded from the primary processor to the secondary processor. According to an embodiment of the present invention, the initialization sequence is then suspended and a discovery process is performed. During the discovery process, it is determined whether the processor running the initialization sequence is a primary or a secondary processor. If it is a secondary processor, then the initialization sequence remains suspended and the secondary processor monitors the health of the primary processor until a failure of the primary processor occurs.

Abstract: The present invention provides a method and system for assigning data chunks to column parity sets in a dual-drive fault tolerant storage disk drive system having N disk drives, where N is a prime number. Each of the N disk drives are organized into N chunks such that the N disk drives are configured as one or more N×N array of chunks. The array has chunks arranged in N rows from row 1 to row N and in N columns from column 1 to column N. Each row includes a plurality of data chunks for storing data, a column parity chunk for storing a column parity set, and a row parity chunk for storing a row parity set. These data chunks are assigned in a predetermined order. The data chunks in each row are assigned to the row parity set. Each column parity set is associated with a set of data chunks in the array, wherein row m is associated with column parity set Qm where m is an integer that ranges from 1 to N.

Abstract: A disc reproducing apparatus reproduces information as a digital signal from a disc, having an interface for sending and receiving a reproduction signal and a command to/from a host computer, comprising a processor unit for controlling the operation of the disc reproducing apparatus, a first signal transfer path, connected to the inter-face, for transferring a command signal corresponding to a command received from the host computer to the processor unit, an operating unit, disposed in the disc reproducing apparatus, for generating an operation signal corresponding to a user's operation, and a second signal transfer path, connected to the operating unit, for transferring an operation signal corresponding to the user's operation of the operating unit to the processor unit, wherein the processor unit determines whether or not to validate the execution of the command of the command signal transferred from the host computer through the first signal transfer path corresponding to the operation signal tra

Abstract: A monitoring system allows users to monitor the post-deployment performance of a web-based or other transactional server. The system includes an agent component (“agent”) which can be installed on computers (“agent computers”) that have access to the transactional server, including computers of actual users of the transactional server. The agent simulates the actions of actual users of the transactional server while monitoring the server's performance. The specific transactions to be performed by the agent computers are specified by testcases that are dispatched to the agent computers using a controller component (“controller”). As each agent computer executes a testcase, it reports the execution results (performance data) in real-time to a web-based reports server which stores the results in a centralized database.

Abstract: A computer network remote data mirroring system writes update data both to a local data device and to a local, chronologically sequenced journal storage area, or writelog device. A primary mirror daemon on a local computer system monitors the writelog device for data updates and feeds the data over a network in the same order in which it is stored to a receiving remote mirror daemon on a remote computer system, which in turn commits the data updates to a mirror device. A graphical user interface enables a user to create and configure throttles. Throttles are user-defined tests and actions evaluated by the primary mirror daemon to regulate network bandwidth, CPU, and writelog device utilization during data update mirroring. Network bandwidth throttling enables a predetermined portion of the network bandwidth to be assigned to remote data mirroring based on user-selected criteria.

Abstract: The present invention relates to a method for testing the operability of a Peer to Peer Remote Copy (PPRC) data storage system in disaster situations. A PPRC data storage system includes a host processor, a primary storage subsystem and a secondary storage subsystem where the secondary storage subsystem is coupled to the primary storage subsystem for mirroring of data therebetween. A command is sent from the host processor directing the primary storage subsystem to simulate a disaster. Upon detection of the disaster, the host establishes direct communication with the secondary storage subsystem, and validates the integrity of the system by comparing data from the secondary storage subsystem to data from the primary storage subsystem.

Abstract: A method for managing a computer system includes initiating a reset of the computer system from a remote location. Diagnostic software on the computer system is downloaded from the remote location.

Abstract: One application of clustered computer systems is to support failover of applications and shared resources. Another is to support scalable or fault-tolerant distributed applications. The present invention utilizes a higher-level clustering mechanism (a multi-cluster) overlayed on top of multiple underlying clusters (subclusters) to extend their capabilities. In the described embodiment, subclusters supporting application and shared resource failover across a smaller number of nodes is overlayed with a multi-cluster supporting a larger number of nodes. The multi-cluster manages cluster-level communication among nodes, and the subclusters directly manage only the shared device and application resources which they are permitted to control. It is possible to move resources between nodes which reside in different subclusters. The multi-cluster layer also externalizes interfaces similar to those of the subclusters, providing application compatibility.

Abstract: Apparatus and methods for correcting protocol errors in computer networking software. More particularly, an apparatus and methods are provided for correcting a class of protocol errors that is compatible with the protocol suite being used in computer networking software. The present invention performs inband protocol correction in a single phase or in multiple phases, according to some specific embodiments.

Abstract: A remote diagnosis system includes a central computer system that receives user data related to a user request and deals with the user request data, and at least one kind of image-forming apparatus connected to the central computer system. Each image-forming apparatus has a user request data input device, through which data related to a user request is optionally input, and a user request data transmitting device that transmits the user request data to the central computer system. A data communication adapter collects the user request data from the at least one kind image forming apparatus and transmits the user request data to the central computer system. An interface interfaces the at least one kind of image-forming apparatus with the data communication adapter, and a public communication network connects the data communication adapter with the central computer system.

Abstract: The invention relates to a method for resetting a processor, and a watchdog for generating a reset pulse to a processor which can initialize itself and which sends acknowledgement pulses at predetermined intervals to the watchdog comprising transmission means (5) for generating and transmitting reset pulses to the processor. The watchdog comprises counter means (7) for counting the number of reset pulses generated during initialization and for setting a predetermined limit value to reset pulses. The watchdog further comprises measuring means (4) for measuring the interval between acknowledgement pulses sent by the processor. In addition, the watchdog comprises transmission means (5) for transmitting a reset pulse when the interval between acknowledgement pulses differs from a predetermined interval.

Abstract: A system and method which provides a complete software implementation of a detection process that is capable of detecting defective Floppy Diskette Controllers (“FDCs”) without visual hardware inspection or identification. The approach taken includes a multi-phase strategy incorporating programmatic FDC identification, software DMA shadowing, defect inducement, and use of a software decoding network which allows the implementation of the invention to adjust to a wide range of computer system performance levels. A method and apparatus for detecting and preventing floppy diskette controller data transfer errors in computer systems is also provided. The approach taken may involve software DMA shadowing and the use of a software decoding network.

Abstract: The present invention, Layered Detection Architecture (“LDA”) is useful to enhance the detection of command control processing errors and also facilitate survivorship among properly functioning flight critical Core Processing Modules (“CPM”) while eliminating faulty CPM responsible for processing execution errors. LDA is contemplated for use with lock-step execution verification schemes and other result comparison command-processing error detection methods also implementing redundant independent processing units.

Abstract: A software record that identifies a software component associated with a processor in a distributed processing system is retrieved from a software configuration database. A check value is calculated for a copy of the software component loaded on the processor. The check value is compared to a second check value retrieved from the software record to verify the software component file.

Abstract: Methods, systems, and devices are provided for managing resources in a computing cluster. The managed resources include cluster nodes themselves, as well as sharable resources such as memory buffers and bandwidth credits that may be used by one or more nodes. Resource management includes detecting failures and possible failures by node software, node hardware, interconnects, and system area network switches and taking steps to compensate for failures and prevent problems such as uncoordinated access to a shared disk. Resource management also includes reallocating sharable resources in response to node failure, demands by application programs, or other events. Specific examples provided include failure detection by remote memory probes, emergency communication through a shared disk, and sharable resource allocation with minimal locking.

Abstract: A method and apparatus for determining proper cabling and identical device locations between two controllers in a RAID system. Each controller first obtains the port names to which it is attached. The list is then reviewed to determine that there are no duplicate entries. Once this step is completed, the controllers exchange their port name lists. The lists are compared to make sure they exactly match. Finally, the controllers exchange a map of the devices themselves present on two channels. The exchange device maps are compared and must be equal. The two device maps being equal indicate that each storage device is logged on to the network through both I/O ports and is available to each controller.