Abstract: In one general embodiment, a computer-implemented method includes querying a database associated with a first cluster of a virtual tape library system for volumes of data stored in the first cluster and querying a second database associated with a second cluster of the virtual tape library system for volumes of data stored in the second cluster. Results of the querying of the database associated with the first cluster are compared with results of the querying of the database associated with the second cluster. The method further includes generating a list of entries of volumes of data that are to be migrated from the first cluster to the second cluster based on the comparing of the results. The entries of the list are ordered according to predefined conditions. The method further includes migrating from the first cluster to the second cluster, copies of the volumes of data of the generated list.

Abstract: In one general embodiment, a computer-implemented method includes querying a database associated with a first cluster of a virtual tape library system for volumes of data stored in the first cluster and querying a second database associated with a second cluster of the virtual tape library system for volumes of data stored in the second cluster. Results of the querying of the database associated with the first cluster are compared with results of the querying of the database associated with the second cluster. The method further includes generating a list of entries of volumes of data that are to be migrated from the first cluster to the second cluster based on the comparing of the results. The entries of the list are ordered according to predefined conditions. The method further includes migrating from the first cluster to the second cluster, copies of the volumes of data of the generated list.

Abstract: Provided are a method, system, and article of manufacture for maintaining message versions at nodes in a network. The nodes in the network maintain version information of nodes in the network. The version information for the nodes indicates a message version number of messages supported at the node. The nodes supporting one message version number can receive messages having that message version number. The nodes use the version information to determine whether there is at least one common message version number among the nodes The nodes supporting the at least one common message version number negotiate to join a quorum of the nodes having the at least one common message version number.

Abstract: An apparatus, system, and method are disclosed for link maintenance. A plurality of state machines operate a plurality of first links between data management nodes with each first link in an online state. A transition module transitions the plurality of first links from the online state to a degraded state and from the online state to an offline pending state in response to an offline request. The transition module further transitions the plurality of first links from the degraded state to an online pending state when a degraded link time interval expires and from the offline pending state to an offline state if all pending tasks on the plurality of first links are completed. The transition module further transitions the plurality of first links from the online pending state to the online state if each first link is validated.

Abstract: A computer processor subsystem, e.g. called a “target”, in response to receiving an update to vital product data of the system from a source computer processor subsystem, examines the update to detect the vital product data of the target computer processor subsystem stored by the source computer processor subsystem; and, in response to the detected vital product data being incorrect, the target computer processor subsystem forwards its correct vital product data to the source computer processor subsystem having the incorrect vital product data. A computer processor subsystem is the authoritative reference for its vital product data.

Abstract: Link information for a plurality of links to at least one target node indicates for each link a send throughput for sending data, a receive throughput for received data, a slate of the link indicating whether the link is online, offline or degraded. The send throughput of the links having the online state is processed to select one of the links to the receiving node m response to determining that more than one of the links has the online state. The data of the send operation is sent using the selected link to the receiving node. The receive throughput is processed to select one of the links having the online state to the sending node in response to determining that more than one of the links has the online state. The data of the receive operation is received using the selected link to the sending node.

Abstract: A method, system, and program product for a VTS subsystem's logging server to optimize applications' logging data entries where applications use the logging service. More specifically, in certain embodiments, the system comprises logic executed within a VTS subsystem to which a tape library subsystem is attached. The logic controls VTS subsystem applications' logging data entry strategy through applications' configured logging level, log entry category, and a cache buffer. The logic not only dynamically balances applications' logging request but also maximizes the availability of system information.

Abstract: An apparatus and system are provided for communicating control messages between a first device and a second device. The apparatus and system include a communication module that directs control messages between a first device and a second device through an intermediate device. The intermediate device is coupled to the first device by a control path and to the second device by a data path. The apparatus and system also include a translation module and a transmission module that cooperate to translate control messages received over the control path at the intermediate device to transport data messages and transport data messages received over the data path at the second device to control messages. Transport data messages are sent over the data path to the second device and control messages from the second device are sent over the control path to the first device.

Abstract: An apparatus, system, and method are disclosed for link maintenance. A plurality of state machines operate a plurality of first links between data management nodes with each first link in an online state. A transition module transitions the plurality of first links from the online state to a degraded state and from the online state to an offline pending state in response to an offline request. The transition module further transitions the plurality of first links from the degraded state to an online pending state when a degraded link time interval expires and from the offline pending state to an offline state if all pending tasks on the plurality of first links are completed. The transition module further transitions the plurality of first links from the online pending state to the online state if each first link is validated.

Abstract: Provided are a method, system, and article of manufacture for using link send and receive information to select one of multiple links to use to transfer data for send and receive operations. Link information for a plurality of links to at least one target node indicates for each link a send throughput for sending data, a receive throughput for received data, a state of the link indicating whether the link is online, offline or degraded. A send operation is processed to transfer data to a receiving node comprising one of the target nodes. A determination is made of the states of the links to the receiving node in response to the send operation. The send throughput of the links having the online state is processed to select one of the links to the receiving node in response to determining that more than one of the links has the online state. The data of the send operation is sent using the selected link to the receiving node.

Abstract: In a system including an application subsystem node having an application RSID table and a logging subsystem node having a logging RSID table, the application subsystem node makes a determination of a registration status of a ALSI string relative to the application RSID table during a logging operation of the ALSI string. The application subsystem node further transfers a RSID package from the application subsystem node across a network to the logging subsystem node, wherein the RSID package includes a RSID encoding of the ALSI string and conditionally includes the ALSI string based on the registration status of the ALIS string relative to the application RSID table as determined by the application subsystem node.

Abstract: An apparatus and system are provided for communicating control messages between a first device and a second device. The apparatus and system include a communication module that directs control messages between a first device and a second device through an intermediate device. The intermediate device is coupled to the first device by a control path and to the second device by a data path. The apparatus and system also include a translation module and a transmission module that cooperate to translate control messages received over the control path at the intermediate device to transport data messages and transport data messages received over the data path at the second device to control messages. Transport data messages are sent over the data path to the second device and control messages from the second device are sent over the control path to the first device.

Abstract: A method, system, and program product for a VTS subsystem's logging server to optimize applications' logging data entries where applications use the logging service. More specifically, in certain embodiments, the system comprises logic executed within a VTS subsystem to which a tape library subsystem is attached. The logic controls VTS subsystem applications' logging data entry strategy through applications' configured logging level, log entry category, and a cache buffer. The logic not only dynamically balances applications' logging request but also maximizes the availability of system information.

Abstract: A data storage and retrieval system is disclosed which includes encoded information regarding known valid system configurations, nominal performance specifications for various I/O devices, and nominal performance specifications for various interconnecting communication buses. A method is disclosed to validate the apparent configuration of the data storage and retrieval system. A method is disclosed to evaluate the performance of each I/O device and interconnecting bus disposed within the data storage and retrieval system.

Abstract: Provided are a method, system, and article of manufacture for maintaining message versions at nodes in a network. The nodes in the network maintain version information of nodes in the network. The version information for the nodes indicates a message version number of messages supported at the node. The nodes supporting one message version number can receive messages having that message version number. The nodes use the version information to determine whether there is at least one common message version number among the nodes The nodes supporting the at least one common message version number negotiate to join a quorum of the nodes having the at least one common message version number.

Abstract: A method for communicating control messages between a first device and a second device. The method includes a communication module that directs control messages between a first device and a second device through an intermediate device. The intermediate device is coupled to the first device by a control path and to the second device by a data path. The method also includes a translation module and a transmission module that cooperate to translate control messages received over the control path at the intermediate device to transport data messages and transport data messages received over the data path at the second device to control messages. Transport data messages are sent over the data path to the second device and control messages from the second device are sent over the control path to the first device.

Abstract: A computer processor subsystem, e.g. called a “target”, in response to receiving an update to vital product data of the system from a source computer processor subsystem, examines the update to detect the vital product data of the target computer processor subsystem stored by the source computer processor subsystem; and, in response to the detected vital product data being incorrect, the target computer processor subsystem forwards its correct vital product data to the source computer processor subsystem having the incorrect vital product data. A computer processor subsystem is the authoritative reference for its vital product data.

Abstract: The process, apparatus, and system estimate the size of a data block in a data buffer to efficiently recover the data block to the memory of a computer. The data block resides in a data buffer prior to being written to a destination medium. If the data block cannot be written to the destination medium, the process, apparatus, and system create a data block size estimate. The data block size estimate may be based on the size of the largest data block in the data buffer. Alternately, the data block size estimate may be based on the size of a data block in the memory of the computer. The computer reserves a memory space proportional to the data block size estimate and recovers the data block to the memory space.

Abstract: The present invention provides fast read performance for accessing a file from a multiplicity of files when its corresponding Block ID is unavailable, by furnishing new file-positioning commands, allowing access to data based on File Number, at the same fast locate speed as with Block Ids, thereby expanding the range of applications that can use certain tape drive systems effectively. The present invention includes both a device architecture for supporting the file oriented positioning and the appending, as well as a software system that can permit easy application access to the device facilities and system components which permit the advantages to accrue without any software application or operator changes, including a robust architecture for navigating residual data, e.g., for data recovery. The present invention comprises several device command innovations, a relative positioning command, an absolute positioning command, and other commands, e.g., for sensing current position.

Abstract: A data storage device having a fixed device architecture capable of operating in a first capacity mode or in a second capacity mode, and capable of switching between that first capacity mode and that second capacity mode. In certain embodiments, the first capacity mode utilizes a 22 bit blockid format and the second capacity mode utilizes a 32 bit blockid format. In other embodiments, the first capacity mode utilizes a 32 bit blockid format and the second capacity mode utilizes a 22 bit blockid format. A data storage device comprising a computer useable medium having computer readable program code disposed therein for recording information in alternative information storage architectures. A data storage and retrieval system which includes one or more of Applicants' data storage devices. A computer code product comprising a data management system which supports the capability to record information on a data storage medium using alternative information storage architectures.