Automated storage library.

摘要

An automated storage library includes four library boxes 1A, 1a, 1B and 1b, each of which contains four optical disk drives 4 and a robotic picker 5. The picker and drives of each box are connected through a switch 60 to two library controllers 17A and 17a. Each library controller 17 maintains an inventory (70) of all storage media in the entire library, but has no disk location inventory. The library controllers are not coupled to each other. Each picker 5 has exclusive access to a set of storage cells and internal peripheral storage devices 4. In addition, a picker controller for each picker maintains a disk location inventory (71) for the disks accessible by such picker. During a failure condition which prevents one library controller from accessing a particular storage medium, the other library controller can be signalled to attempt to access such storage medium. <IMAGE>