OVERVIEW

Enstore provides distributed access to and management of Petabytes of data stored on tape. The data can be made of up to billions of files of varying sizes - typically of between 1 and 5 Gigabytes in size. At any time, many of the tapes are accessible through automated tape libraries. The system supports migration of tapes to and from shelves - export and import - where operator intervention is required to move the tapes between the shelves and roboticly accessible tape drives.

The Enstore system provides for access to the data by user/client applications which are distributed across an IP network. It supports tape drives attached locally to the users' computer, as well as those remotely accessible over the network.

The Enstore system provides resource management of the available tape drives such that, for example, logging of data from the data acquisition systems can be given guaranteed access to the tape bandwidth whatever other user accesses are being requested.

The Enstore system is designed to provide for the needed Run II data access throughput requirements within the budget assigned (reference..). The system is modular to the extent that those components needed by remote institutions - who do not have access to the primary data source - can be used independently and without significant cost. The system software is layered and accessible to the Run II developers such that needed modifications can be made in a timely manner to meet the needs of commissioning and running of the Run II detectors.

Enstore is designed to support "lights out" operation of the Run II automated tape library systems. To this end the design is targeted towards requiring operator intervention at no more than 8 hour intervals - for example, to queue import/export requests to be handled only within the day time operator shifts. Careful attention is paid to error reporting, handling and recovery in order to require the minimal possible load on the operations and support staff.

Enstore is designed to be used by Fermilab experiments data acquisition, data processing and analysis systems. Well defined interfaces will be provided to these data handling systems to allow them to easily use the services provided.