No abstract

This paper is concerned with the overall design of the Terabit File Storea network storage facility based on a Braegen Automated Tape Library. The characteristics of the tape libraryin particular its large capacity and slow accessprovide both challenges and opportunities for the system designer. The use of disc cache and the optimization of file placement have been used to provide reasonable performance in the face of substantial tape handling times. Catalogue facilities have been tailored to cater for the support of large file holdings and user file back-up applications. It has been possible to automate the back-up of essential file-store information which together with automatic integrity checks, helps to minimize the damage that can be caused by faults. Considerable attention has been given to facilities that automate much of the management of the system in a network environment. Other aspects of the design discussed in the paper include protection, housekeeping and host interfacing. KEY WORDS File store Large scale storage Automation Tape library Network Cache Australian Government research organization with over 7000 employees at 50 sites around the country. The CSIRO Division of Computing Research (DCR) runs the CSIRONET computing service for use by CSIRO, government and other users. Major host computers on the network are a Cyber 76 running SCOPE 2, a Cyber 835 running 0038-0644/85/090889-1 lj601.10 0 1985 by John Wiley tk Sons, Ltd.