Abstract: An apparatus, method, and computer program for maintaining access times in a data processing system, wherein the data processing system comprises a plurality of storage devices, the apparatus including: a receive component, for receiving a command or an availability message, wherein an availability message indicates whether the storage device is available; an evaluate component for evaluating a plurality of first relationships between the storage devices and a plurality of first values, wherein each of the first values indicates whether a related storage device is a redundant; a send component, for sending a power message to one or more of the storage devices; and an update component for updating a second relationship between the redundant storage device and a plurality of second values, wherein each of the second values indicates whether a related redundant storage device is available.

Abstract: An apparatus, method, and computer program for maintaining access times in a data processing system, wherein the data processing system comprises a plurality of storage devices, the apparatus including: a receive component, for receiving a command or an availability message, wherein an availability message indicates whether the storage device is available; an evaluate component for evaluating a plurality of first relationships between the storage devices and a plurality of first values, wherein each of the first values indicates whether a related storage device is a redundant; a send component, for sending a power message to one or more of the storage devices; and an update component for updating a second relationship between the redundant storage device and a plurality of second values, wherein each of the second values indicates whether a related redundant storage device is available.

Abstract: An apparatus, method, and computer program for maintaining access times in a data processing system, wherein the data processing system comprises a plurality of storage devices, the apparatus including: a receive component, for receiving a command or an availability message, wherein an availability message indicates whether the storage device is available; an evaluate component for evaluating a plurality of first relationships between the storage devices and a plurality of first values, wherein each of the first values indicates whether a related storage device is a redundant; a send component, for sending a power message to one or more of the storage devices; and an update component for updating a second relationship between the redundant storage device and a plurality of second values, wherein each of the second values indicates whether a related redundant storage device is available.

Abstract: An apparatus, method, and computer program for maintaining access times in a data processing system, wherein the data processing system comprises a plurality of storage devices, the apparatus including: a receive component, for receiving a command or an availability message, wherein an availability message indicates whether the storage device is available; an evaluate component for evaluating a plurality of first relationships between the storage devices and a plurality of first values, wherein each of the first values indicates whether a related storage device is a redundant; a send component, for sending a power message to one or more of the storage devices; and an update component for updating a second relationship between the redundant storage device and a plurality of second values, wherein each of the second values indicates whether a related redundant storage device is available.

Abstract: A method and apparatus for relating a device name to a physical location of a device (202) on a network is provided. The network may be a serial loop network, for example a Fibre Channel Arbitrated Loop network. The network includes a plurality of devices (202) on or connected to the network (201) and a control device (205) with control over at least one of the devices (202). Each device (202) has a check output (204) independent of the network (201) with connection means (206) to a control device (205). The method includes the step of sending a device name from the check output (204) of a device (202) to the control device (205). The check output (204) of a device (202) is also connected to an external indication means for indicating the failure of the device (202).

Abstract: A method and apparatus for recovery from faults in a loop network (500) is provided. The loop network (500) has a plurality of ports (520, 530, 532, 534) serially connected with means for bypassing the ports (520, 530, 532, 534) from the loop network (500). A control device (522, 524) is provided with bypass control over at least one of the ports (530, 532, 534). A host means (502) sends a command to the control device (522, 524) at regular intervals and the control device (522, 524) has a counter which restarts a time period at the receipt of each command. If the time period expires, the control device (522, 524) activates the means for bypassing all the ports (530, 532, 534) under its control. The loop network (500) may have two loops (516, 518) with at least some of the ports (520, 530, 532, 534) common to both loops (516, 518).

Abstract: A method and apparatus for relating a device name to a physical location of a device (202) on a network is provided. The network may be a serial loop network, for example a Fibre Channel Arbitrated Loop network. The network includes a plurality of devices (202) on or connected to the network (201) and a control device (205) with control over at least one of the devices (202). Each device (202) has a check output (204) independent of the network (201) with connection means (206) to a control device (205). The method includes the step of sending a device name from the check output (204) of a device (202) to the control device (205). The check output (204) of a device (202) is also connected to an external indication means for indicating the failure of the device (202).

Abstract: A method and apparatus for relating a device name to a physical location of a device (202) on a network is provided. The network may be a serial loop network, for example a Fibre Channel Arbitrated Loop network. The network includes a plurality of devices (202) on or connected to the network (201) and a control device (205) with control over at least one of the devices (202). Each device (202) has a check output (204) independent of the network (201) with connection means (206) to a control device (205). The method includes the step of sending a device name from the check output (204) of a device (202) to the control device (205). The check output (204) of a device (202) is also connected to an external indication means for indicating the failure of the device (202).

Abstract: A method and apparatus for detection of a port name in a loop network is provided, particularly a loop network in the form of a Fibre Channel Arbitrated Loop (FC-AL). The loop network (100) has a plurality of devices (120) each device (120) having at least one port (211, 212) on the loop network (100). The method includes determining which ports (211, 212) are populated with devices (120) for which the unique port name (WWPN) is not known. The populated ports are then all bypassed and a mode is entered on the loop network (100) in which idle frames are transmitted around the loop network (100). One port is un-bypassed at a time and the port name from the un-bypassed port is received and recorded. The port name is received from the un-bypassed port in a Loop Initialisation Select Master (LISM) frame transmitted by the un-bypassed port.

Abstract: A method and apparatus for detection of a port name in a loop network is provided, particularly a loop network in the form of a Fibre Channel Arbitrated Loop (FC-AL). The loop network (100) has a plurality of devices (120) each device (120) having at least one port (211, 212) on the loop network (100). The method includes determining which ports (211, 212) are populated with devices (120) for which the unique port name (WWPN) is not known. The populated ports are then all bypassed and a mode is entered on the loop network (100) in which idle frames are transmitted around the loop network (100). One port is un-bypassed at a time and the port name from the un-bypassed port is received and recorded. The port name is received from the un-bypassed port in a Loop Initialisation Select Master (LISM) frame transmitted by the un-bypassed port.

Abstract: A method and apparatus for recovery from faults in a loop network (500) is provided. The loop network (500) has a plurality of ports (520, 530, 532, 534) serially connected with means for bypassing the ports (520, 530, 532, 534) from the loop network (500). A control device (522, 524) is provided with bypass control over at least one of the ports (530, 532, 534). A host means (502) sends a command to the control device (522, 524) at regular intervals and the control device (522, 524) has a counter which restarts a time period at the receipt of each command. If the time period expires, the control device (522, 524) activates the means for bypassing all the ports (530, 532, 534) under its control. The loop network (500) may have two loops (516, 518) with at least some of the ports (520, 530, 532, 534) common to both loops (516, 518).

Abstract: A method and apparatus for recovery from faults in a loop network (400) is provided. The loop network (400) has a host means (402), a first loop and a second loop (406, 408), a plurality of ports (410) connected to each of the loops (406, 408) and a control device (414, 440) on or connected to each loop (406, 408) with bypass control over at least one of the ports (410) connected to the loop (406, 408). In the event of a failure on the first loop (406), the host means (402) instructs the bypassing of at least one port (410) on the first loop (406), the host means (402) sending the instructions via the control device (414, 440) on or connected to the second loop (408).

Abstract: A method and apparatus for recovery from faults in a loop network (500) is provided. The loop network (500) has a plurality of ports (520, 530, 532, 534) serially connected with means for bypassing the ports (520, 530, 532, 534) from the loop network (500). A control device (522, 524) is provided with bypass control over at least one of the ports (530, 532, 534). A host means (502) sends a command to the control device (522, 524) at regular intervals and the control device (522, 524) has a counter which restarts a time period at the receipt of each command. If the time period expires, the control device (522, 524) activates the means for bypassing all the ports (530, 532, 534) under its control. The loop network (500) may have two loops (516, 518) with at least some of the ports (520, 530, 532, 534) common to both loops (516, 518).

Abstract: A data storage system includes a host computer, a data storage device, and a communication bus connecting the host computer to the data storage device. The host computer is adapted to issue a specialized initiation command, such as a format command with a unique parameter or a unique send diagnostic command. Once received by the data storage device, the specialized initiation command is decoded by a command processor which, in turn, directs a memory controller to execute an internal initiation of target sectors residing on data storage media within the data storage device. The memory controller places sector data in a temporary memory device, such as a random-access memory (“RAM”), including a plurality of zeroes appended to a logical redundancy check (“LRC”) value. Once compiled, this sector data is written to the data storage media. In this way, target sectors of the data storage media are initialized with LRC information without requiring large amounts of data being transmitted over the communication bus.

Abstract: A method and apparatus are provided for fault location in a loop network (100, 200, 400). The network system having a host port (214) for supplying and receiving data and a plurality of successively connected ports (201, 202, 203, 204, 205) through which data from the host port (214) is transferred. A counter (122) for each port records data transfers in which the amount of data received at a destination port is less than an expected amount of data. When a transfer with less than the expected amount of data is identified for a data flow between a sending port (201) and a destination port (214), the counters are incremented for each port (202, 203, 204, 205, 214) after the sending port up to and including the destination port. Analysing means determines a fault location in the network system from the distribution of counts in the counters (122).

Abstract: A method and apparatus for relating a device name to a physical location of a device (202) on a network is provided. The network may be a serial loop network, for example a Fibre Channel Arbitrated Loop network. The network includes a plurality of devices (202) on or connected to the network (201) and a control device (205) with control over at least one of the devices (202). Each device (202) has a check output (204) independent of the network (201) with connection means (206) to a control device (205). The method includes the step of sending a device name from the check output (204) of a device (202) to the control device (205). The check output (204) of a device (202) is also connected to an external indication means for indicating the failure of the device (202).

Abstract: A method and apparatus are provided for hard address conflict resolution for enclosures in a loop network (200). The loop network (200) has: a loop (202); a host means (201) on or connected to the loop (202); a plurality of devices (207) on or connected to the loop (202); and at least one enclosure containing one or more devices (207). Each device (207) has an address means. Each enclosure has an enclosure control device (208) with control over devices (207) in that enclosure. Each enclosure control device (208) has an address means. The method includes, at the start up of the loop network (200), setting the address means of the enclosure control devices (208) to a default value. Each device (207) is then entered in the loop (202) in a reset state in which only the enclosure control devices (208) and the host means (201) are active in the loop (202).

Abstract: A method and apparatus for detection of a port name in a loop network is provided, particularly a loop network in the form of a Fibre Channel Arbitrated Loop (FC-AL). The loop network (100) has a plurality of devices (120) each device (120) having at least one port (211, 212) on the loop network (100). The method includes determining which ports (211, 212) are populated with devices (120) for which the unique port name (WWPN) is not known. The populated ports are then all bypassed and a mode is entered on the loop network (100) in which idle frames are transmitted around the loop network (100). One port is un-bypassed at a time and the port name from the un-bypassed port is received and recorded. The port name is received from the un-bypassed port in a Loop Initialisation Select Master (LISM) frame transmitted by the un-bypassed port.

Abstract: A method and apparatus are provided for fault location in a loop network (100, 200, 400). The network system having a host port (214) for supplying and receiving data and a plurality of successively connected ports (201, 202, 203, 204, 205) through which data from the host port (214) is transferred. A counter (122) for each port records data transfers in which the amount of data received at a destination port is less than an expected amount of data; When a transfer with less than the expected amount of data is identified for a data flow between a sending port (201) and a destination port (214), the counters are incremented for each port (202, 203, 204, 205, 214) after the sending port up to and including the destination port. Analysing means determines a fault location in the network system from the distribution of counts in the counters (122).

Abstract: A method and apparatus for recovery from faults in a loop network (400) is provided. The loop network (400) has a host means (402), a first loop and a second loop (406, 408), a plurality of ports (410) connected to each of the loops (406, 408) and a control device (414, 440) on or connected to each loop (406, 408) with bypass control over at least one of the ports (410) connected to the loop (406, 408). In the event of a failure on the first loop (406), the host means (402) instructs the bypassing of at least one port (410) on the first loop (406), the host means (402) sending the instructions via the control device (414, 440) on or connected to the second loop (408).