Abstract: A system and method of media library access that utilizes distributed mapping of media library partitions. A first controller can be connected to a data transport element of a media library and a second controller can be connected to a media changer of the media library. The first controller can maintain a media library partition representing a portion of the media library, receive a command from a host application based on the media library partition and forward the command to the second controller. The first controller can further translate logical addresses referenced in the command to physical addresses before forwarding the command to the second controller. The second controller can receive the command from the first controller and forward the command to the media changer. The second controller can also prioritize the command on using a FIFO or other prioritization scheme.

Abstract: Embodiments of the present invention provide a media library controller that can communicate with multiple physical libraries that are physically separate from each other (i.e., that cannot pass media back and forth). The media library controller can maintain a virtualized aggregate media library representing the physical media libraries with which it is in communication. From the physical media libraries, the media library controller can establish a virtual media library and associate a host with the virtual media library. The virtual media library can represent the portions of a physical media library to which the host is allowed access.

Abstract: Embodiments of the present invention provide an interface device and method for command processing for commands requiring data flow in both directions on a Fiber Channel or other data transport protocol exchange. The commands can include proprietary commands, SCSI linked commands or other commands known in the art. According to one embodiment, and interface device can assign a command a data flow direction indicator. When a reply to the command is received, the interface device can determine if the reply is expected or unexpected based on the data flow direction specified by the data flow direction indicator. If the reply is unexpected, the interface device can determine whether to process the reply. According to one embodiment, the data flow direction indicator can be the exchange identification.

Abstract: Embodiments of the present invention provide an interface device and method for command processing for commands requiring data flow in both directions on a Fiber Channel or other data transport protocol exchange. The commands can include proprietary commands, SCSI linked commands or other commands known in the art. According to one embodiment, and interface device can assign a command a data flow direction indicator. When a reply to the command is received, the interface device can determine if the reply is expected or unexpected based on the data flow direction specified by the data flow direction indicator. If the reply is unexpected, the interface device can determine whether to process the reply. According to one embodiment, the data flow direction indicator can be the exchange identification.

Abstract: A system and method of media library access that utilizes distributed mapping of media library partitions. A first controller can be connected to a data transport element of a media library and a second controller can be connected to a media changer of the media library. The first controller can maintain a media library partition representing a portion of the media library, receive a command from a host application based on the media library partition and forward the command to the second controller. The first controller can further translate logical addresses referenced in the command to physical addresses before forwarding the command to the second controller. The second controller can receive the command from the first controller and forward the command to the media changer. The second controller can also prioritize the command on using a FIFO or other prioritization scheme.

Abstract: A system and method of media library access that utilizes distributed mapping of media library partitions. A first controller can be connected to a data transport element of a media library and a second controller can be connected to a media changer of the media library. The first controller can maintain a media library partition representing a portion of the media library, receive a command from a host application based on the media library partition and forward the command to the second controller. The first controller can further translate logical addresses referenced in the command to physical addresses before forwarding the command to the second controller. The second controller can receive the command from the first controller and forward the command to the media changer. The second controller can also prioritize the command using a FIFO or other prioritization scheme.

Abstract: Embodiments of the present invention provide a system and method for handling persistent reservations. More particularly, according to one embodiment of the present invention, a routing device that routes commands from multiple initiators to a target device can assert reservations for the initiators using its own reservation key rather than a reservation key provided by an initiator. The routing device can further maintain a registry of keys for multiple initiators that access the target device through the routing device. For a persistent reservation command received using a persistent reservation key in the registry, the routing device can forward the command to the target device server using the routing device's key. Thus, reservations for the multiple initiators will be held using the routing device's key. For persistent reservation commands received from initiators registered with the routing device, the routing device can handle conflict resolution and other persistent reservation processing.

Abstract: Embodiments of the present invention provide an interface device and method for command processing for commands requiring data flow in both directions on a Fiber Channel or other data transport protocol exchange. The commands can include proprietary commands, SCSI linked commands or other commands known in the art. According to one embodiment, an interface device can assign a command a data flow direction indicator. When a reply to the command is received, the interface device can determine if the reply is expected or unexpected based on the data flow direction specified by the data flow direction indicator. If the reply is unexpected, the interface device can determine whether to process the reply. According to one embodiment, the data flow direction indicator can be the exchange identification.

Abstract: Embodiments of a routing device for coordinating the interoperability of devices with varying capabilities that send and/or receive commands in a storage network are disclosed. A host device in the storage network may inquire the capabilities of a storage device in a storage network. A routing device may receive a response from the storage device and pass the response through to the host unaltered or may alter the response to reflect the higher or lower capabilities of the routing device before sending the response to the host.

Abstract: Embodiments of the present invention provide a media library controller that can communicate with multiple physical libraries that are physically separate from each other (i.e., that cannot pass media back and forth). The media library controller can maintain a virtualized aggregate media library representing the physical media libraries with which it is in communication. From the physical media libraries, the media library controller can establish a virtual media library and associate a host with the virtual media library. The virtual media library can represent the portions of a physical media library to which the host is allowed access.

Abstract: Embodiments of the present invention provide a media library controller that can communicate with multiple physical libraries that are physically separate from each other (i.e., that cannot pass media back and forth). The media library controller can maintain a virtualized aggregate media library representing the physical media libraries with which it is in communication. From the physical media libraries, the media library controller can establish a virtual media library and associate a host with the virtual media library. The virtual media library can represent the portions of a physical media library to which the host is allowed access.

Abstract: Embodiments of the present invention provide for conversion between command protocols. A routing device, or other device in the command path, can receive a command from an initiator, determine if the initiator and target for the command support the same command protocol and, if not, convert the command and/or response between the command protocols used by the initiator and the target. For commands not supported by the target or for particular predetermined commands, the device can generate a response to the command rather than passing the command to the target. Additionally, the device can modify responses from the target to include additional data and indications of errors according to the command protocol supported by the initiator.

Abstract: Embodiments of the present invention provide a system and method of media library access that eliminates, or at least substantially reduces, the shortcomings of prior art media library access systems and methods. More particularly, embodiments of the present invention provide systems and methods of distributed mapping of media library partitions. According to one embodiment, the present invention can include a first controller connected to a data transport element of a media library and a second controller connected to a media changer of the media library. The first controller can maintain a media library partition representing a portion of the media library, receive a command from a host application based on the media library partition and forward the command to the second controller. The first controller can further translate logical addresses referenced in the command to physical addresses before forwarding the command to the second controller.

Abstract: Embodiments of the present invention provide a system and method of media library access that eliminates, or at least substantially reduces, the shortcomings of prior art media library access systems and methods. More particularly, embodiments of the present invention provide systems and methods of distributed mapping of media library partitions. According to one embodiment, the present invention can include a first controller connected to a data transport element of a media library and a second controller connected to a media changer of the media library. The first controller can maintain a media library partition representing a portion of the media library, receive a command from a host application based on the media library partition and forward the command to the second controller. The first controller can further translate logical addresses referenced in the command to physical addresses before forwarding the command to the second controller.

Abstract: Embodiments of the present invention provide systems and methods of centralized mapping of media library partitions. According to one embodiment, the present invention can include a first controller connected to a data transport element of a media library and a second controller connected to a media changer of the media library. The first controller can receive a command from a host application based on a media library partition presented to that host and forward the command to the second controller. The second controller can receive the command from the first controller, translate logical addresses referenced in the command to physical addresses and forward the command to the media changer. The second controller, can also prioritize the command on a FIFO basis or according to other prioritization scheme known in the art.

Abstract: Systems and methods for coordinating the interoperability of devices in a network are disclosed. Embodiments of the present invention may provide the ability for a host device in a storage network to inquire as to the capabilities of a storage device in a storage network. A routing device between the host and the storage device may receive a response, and if the routing device has a higher capability than the storage device the routing device may convert the response to a response that reflects the higher capabilities of the routing device before sending the response on to the host. However, if the storage device has a higher capability than the routing device, the routing device may pass the response through to the host unaltered.

Abstract: Systems and methods for performing error recovery in a system utilizing redundant communication links. In one embodiment, a host device is coupled to a sequential device such as a tape drive by a pair of Fiber Channel links. The host is configured to associate an identifier with each command. Upon detecting a failure of the transmission of the command via the first link, the host re-transmits the command via the second link. When the link failure is detected, the status of the last command transmitted before the failure is requested. After receiving the status of the command, a request that recovery start (possibly at a point indicated by the status information) is transmitted to the sequential device. If the recovery request is accepted, performance of the command is completed.

Abstract: Systems and methods for coordinating the interoperability of devices with varying capabilities are disclosed. A host device may inquire as to the capabilities of a storage device in a storage network. A routing device may receive this response, and if the routing device has a higher capability than the storage device the routing device may convert the response to a response that reflects the higher capabilities of the routing device before sending the response on to the host. However, if the storage device has a higher capability than the routing device, the routing device may pass the response through to the host unaltered so the host may take advantage of the capabilities of the storage device. Alternatively, the router may convert the response to a response that reflects the lower capabilities of the routing device before sending the response on to the host.

Abstract: Systems and methods for reducing the number of unit attentions provided to a set of initiator devices by eliminating unnecessary unit attentions from queues in which unit attentions for each of the initiator devices are stored. In one embodiment, a system comprises a processor and a memory implemented in a router that is coupled between a target device and multiple initiator devices. As each unit attention is generated by the target device, it is forwarded to the initiator device that prompted the unit attention, and is stored in a queue for each of the other initiator devices. Periodically, the queues are examined to determine whether any of the unit attentions stored therein are unnecessary. One or more of the unit attentions that are determined to be unnecessary may be eliminated from the respective queues, reducing the number of unit attentions that are provided to the respective initiator devices.

Abstract: Systems and methods for performing error recovery in a system utilizing redundant communication links. In one embodiment, a host device is coupled to a sequential device such as a tape drive by a pair of Fibre Channel links. The host is configured to associate an identifier with each command. Upon detecting a failure of the transmission of the command via the first link, the host re-transmits the command via the second link. When the link failure is detected, the status of the last command transmitted before the failure is requested. After receiving the status of the command, a request that recovery start (possibly at a point indicated by the status information) is transmitted to the sequential device. If the recovery request is accepted, performance of the command is completed.