Abstract: Described are techniques for processing a network connectivity request received by a virtual network connectivity service. First processing is performed by the virtual network connectivity service to service the network connectivity request. The first processing includes determining a first of a plurality of network control planes to which the network connectivity request is directed, selecting, in accordance with the first network control plane, one of a plurality of modules, and invoking the one module in connection with performing processing to service the network connectivity request.

Abstract: Described are techniques for determining connectivity. Statistics are received regarding components of the data storage system including any of a target port, a front end adapter, and a device. It is determined in accordance with inputs whether to modify existing connectivity between an initiator set of one or more initiators and a target set of one or more target ports of the data storage system. The inputs include the one or more statistics and one or more adjustment criteria. Responsive to determining to modify the existing connectivity, first processing makes modification(s) to the existing connectivity including any of: modifying an access state associated with a target port over which a device is exposed to an initiator, and adding or removing connectivity between the initiator and another target port of the data storage system where a device is exposed to the initiator over the another target port.

Abstract: This invention is a system and method for managing data in a secure manner in a data storage environment that is in communication with a network including an internet-based network. The system includes logic for securely managing internet client's access to data volumes stored on a data storage system, and may also include logic operating with a file server for providing dynamic access of data available to such clients in a secure fashion.

Abstract: A data management technique for managing accesses to data at a shared storage system includes a filter at the storage system. The filter is coupled to a configuration table, which identifies which of a number of coupled host processors have accesses to each of the resources at the device. During operation, requests received from the host devices are filtered by the filter, and only those requests to resources that the individual host devices have privilege to access are serviced. Advantageously, data security is further enhanced by authenticating each of the requests received by the storage system to verify that the host processor that is represented as forwarding the request is the indicated host processor. In addition, transfers of data between the storage system and the host processor may be validated to ensure that data was not corrupted during the data transfer.

Abstract: This invention is a system and for managing data in a secure manner in a data storage environment that is in communication with a network including an internet-based network. The system includes computer-executable logic or software for securely managing internet client's access to data volumes stored on a data storage system, and may also include logic operating with a file server for providing dynamic access of data available to such client's in a secure fashion.

Abstract: A data management technique for managing accesses to data at a shared storage system includes a filter at the storage system. The filter is coupled to a configuration table, which identifies which of a number of coupled host processors have accesses to each of the resources at the device. During operation, requests received from the host devices are filtered by the filter, and only those requests to resources that the individual host devices have privilege to access are serviced. Advantageously, data security is further enhanced by authenticating each of the requests received by the storage system to verify that the host processor that is represented as forwarding the request is the indicated host processor. In addition, transfers of data between the storage system and the host processor may be validated to ensure that data was not corrupted during the data transfer.

Abstract: A method for handling data in a plurality of data storage disks having user data sectors and corresponding parity sectors, the method being used when the disks are being operated in a non-degraded or a degraded mode wherein a non-volatile RAM is used in an array control processor which controls the operation of such disks. When new data is to be written into the array, the non-volatile RAM stores information identifying the array, the starting sector into which data is to be written and the number of sectors to be used for writing the new data so that parity and data entries in corresponding sectors can be matched when a power failure occurs. Further, when opening a new array, the data and parity entries in corresponding sectors can be matched and verified, the operation for such matching being performed in between other operations that are being performed by the control processors (i.e., in the "background" thereof).

Abstract: A method for providing on-line replacement of a module which is at a specified position in an array of modules connected to a common control processor so that all other modules in the array can continue operating during the replacement operation. When the module is removed an indication is provided to the control processor showing that removal has occurred and identifying the position thereof. When the replacement has occurred an indication thereof is provided to the control processor, the replacement module is tested, and the state of the replacement module is updated to place it in the same state it would have been in if it had not been replaced.

Abstract: An apparatus provides a sequence detected signal indicating that a synchronization sequence occurring at regular intervals in a stream of data has occurred or should have occurred. The apparatus includes logic for detecting the synchronization sequence, logic responsive to the detection logic for producing the sequence detected signal when the detection logic detects the sequence, and logic for producing the sequence detected signal at a fixed time after the synchronization sequence should have occurred. If the synchronization sequence did occur, the apparatus thus produces two sequence detected signals; however, the device receiving the sequence detected signal responds to the first sequence detected signal and ignores the second. If the synchronization sequence did not occur, the device receiving the sequence detected signal responds to the sequence detected signal produced by the logic responsive to the timing apparatus.

Abstract: Disk drive control apparatus for controlling operation of a disk drive. The disk drive control apparatus has hierarchical control and includes control apparatus for controlling other components of the disk drive control apparatus, a controller interface receiving a bus connecting the disk drive control apparatus to a controller, a read-write processor for processing data received from or read to the disk, and data transfer apparatus for transferring data alternatively between the bus connected to the controller interface and the read-write processor, between the bus and the control apparatus, and between the read-write processor and the control apparatus. The control apparatus receives operational instructions from the controller via the bus, and responds to the operational instructions by providing internal instructions for the data transfer apparatus and the read-write processor.

Abstract: Logic circuitry for use in electrical apparatus for providing an interrupt signal to a controller when there is a power failure in the electrical apparatus. The logic circuitry is connected to a bus from the controller. When the logic circuitry receives a power failure signal, it sets an interrupt state register and provides an interrupt signal on the bus as long as the interrupt state register is set. If the power failure signal no longer indicates a power failure, the logic circuitry responds to a signal from the controller indicating that the interrupt has been received by resetting the interrupt state register, thereby ending the interrupt. However, if the power failure signal is still active, the logic circuitry will not reset the interrupt state register in response to the signal from the controller.

Abstract: A method useful in a disk drive for diagnosing malfunctions in the path by which data codes are encoded into disk codes and written to the disk and by which disk codes are read from the disk and decoded into data codes. The disk drive in which the method is used includes control apparatus having a memory for controlling operation of the disk drive, a read-write processor for translating data codes to disk codes and vice-versa, and data transfer means including a memory for transferring data codes internally in the disk drive. In the method, a copy of a test pattern stored in the memory belonging to the control apparatus is made and provided to the memory in the data transfer means. It is provided from then to the read-write processor, which translates the data codes in the copy to disk codes and writes them to a diagnostic track on the disk. The disk codes are then read from the diagnostic track and translated by the read-write processor.

Abstract: A digital data bus system for connecting a controller and a disk drive. Data on the disk is stored in track sectors containing a header and data. The controller includes a high-speed processor which performs a header compare operation comparing the values received from a header with the expected contents of the header and operations which determine when all of the data in a track sector has been transferred. The digital data bus system includes a bus for transferring data between the controller and the disk drive and a header-data mode bus for providing a header mode signal and a data mode signal from the controller to the disk drive. During an operation transferring data between the controller and the disk, the disk drive responds to the header mode signal by transferring a header to the controller.