Abstract: Systems and methods that dynamically distribute status, cartridge movement and other types of requests and communications from a library manager to one or more libraries of a library string based on target or subject libraries in the requests. Upon receiving and/or generating a request, the library manager determines whether active connections (e.g., control paths) are available from the library manager substantially directly to the subject libraries and then distributes the requests over such active connections when available. When such active connections are unavailable, the library manager may distribute such requests over active connections to non-subject libraries which may forward such requests to the subject libraries via an inter-library communication interconnect.

Abstract: Systems and methods that dynamically distribute status, cartridge movement and other types of requests and communications from a library manager to one or more libraries of a library string based on target or subject libraries in the requests. Upon receiving and/or generating a request, the library manager determines whether active connections (e.g., control paths) are available from the library manager substantially directly to the subject libraries and then distributes the requests over such active connections when available. When such active connections are unavailable, the library manager may distribute such requests over active connections to non-subject libraries which may forward such requests to the subject libraries via an inter-library communication interconnect.

Abstract: A write protect device for a computer comprising a hardware circuit with a switch connected to an internally installed circuit card which has cable connections between data storage device drives and a drive controller cable, the circuit card intercepting control lines used for drive selection and control. The switch is connected to inputs of a latch circuit which, in one position of the switch, generates *READONLY and READONLY signals at outputs of the latch circuit and, in a second position, *DISABLE and DISABLE signals at other outputs. To enter a read only mode, the circuit card includes an inverter and a NAND gate in a *WRITE GATE line to the data storage device drives with one input of the NAND gate being connected to the *READONLY line from the latch circuit which will prevent any *WRITE GATE signal from reaching the data storage device drives when the *READONLY line is activated.