Abstract: An automated storage library for which the management thereof is transparent to a requester is disclosed. The library provides for all of its own internal management. To access a file in the library, a requester need only specify the volume on which the file is located, permitting the use of a standard file access method for a single peripheral storage device. A path format which is the same as that used for a single, peripheral storage device, except that the peripheral storage device designator is replaced with a designator for the automated storage library and a volume label is inserted as a subdirectory path element, and a program product therefor are also disclosed.

Abstract: A method for servicing a mount request in an automated storage library in which all of the peripheral storage devices therein are occupied and which permits an active data storage medium to be temporarily demounted and subsequently remounted in any subsequently available peripheral storage device is disclosed. To service a mount request requiring that a data storage medium be demounted, the access information for the data storage medium to be demounted is first retained. After demounting and servicing of the mount request, the retained access information is used to permit remounting of the previously mounted data storage medium in any subsequently available peripheral storage device, thereby minimizing the risk of delay in remounting. The method also allows for optional parameters to prevent temporary demounting in an automated storage library, or to prevent temporary demounting of particular data storage media. An automated storage library and program product employing the method are also disclosed.

Abstract: An optical disk having its disk inventory at the picker level is disclosed. The library includes two library controllers and four pickers. Each library controller maintains a list of the storage media in the entire library, but has no disk location inventory. The library controllers are not coupled to each other. Each picker has exclusive access to a set of storage cells and internal peripheral storage devices. In addition, the picker controller for each picker maintains the disk location inventory 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. The overhead associated with maintaining two identical copies of the inventory in the library controllers is therefore eliminated.

Abstract: A method for selecting data storage media for demount in an automated storage library, and an automated storage library and program product therefor are disclosed. Preemptive demount of storage media is permitted when all peripheral storage devices in the library are occupied and one or more of such devices remains inactive for a predetermined time. Storage media may be demounted to service existing mount requests, provide the peripheral storage devices in which the media are mounted are inactive. There is also a need, however, to ensure the availability of an empty device to service future mount requests, particularly in libraries having only a single gripper mechanism. Thus, even when no mount requests are pending, the status of the peripheral storage devices is continually monitored.

Abstract: A method for selecting additional data storage media for demount in an idle automated storage library, and an automated storage library and program product therefor are disclosed. The method permits the advanced demount of storage media when one or more of the occupied peripheral storage devices remains inactive for a relatively long predetermined time. Storage media may be demounted to service a pending mount request, provided the peripheral storage devices in which the media are mounted are inactive. A storage medium may also be demounted to create an unoccupied peripheral storage device, even though no mount request is pending, when all of the peripheral storage devices are occupied and one or more of such devices remains inactive for a relatively short predetermined time.

Abstract: An error recovery subsystem which can be easily modified for use with any physical hardware which is being monitored is disclosed. The error recovery subsystem employs a user editable file including the rules for defining the system state, the error states, and the sequences of recovery actions to be taken depending upon the comparison between the system state and the error states. The rules for defining the system state, include don't care variables, and the sequences of recovery actions are specified using an index into a set of elemental recovery actions. Because the system state, error state, and sequence of recovery actions are defined in a user editable file modifications to the error recovery scheme can be made without recompiling the error recovery subsystem program code. Such modifications to the error recovery subsystem may therefore be made on a real time basis. A method for recovering from an error and a program product therefore are also disclosed.

Abstract: A method for servicing a mount request in an automated storage library in which all of the peripheral storage devices therein are occupied and which permits an active data storage medium to be temporarily demounted and subsequently remounted in any subsequently available peripheral storage device is disclosed. To service a mount request requiring that a data storage medium be demounted, the access information for the data storage medium to be demounted is first retained. After demounting and servicing of the mount request, the retained access information is used to permit remounting of the previously mounted data storage medium in any subsequently available peripheral storage device, thereby minimizing the risk of delay in remounting. The method also allows for optional parameters to prevent temporary demounting in an automated storage library, or to prevent temporary demounting of particular data storage media. An automated storage library and program product employing the method are also disclosed.