Abstract: A method and apparatus for sharing a single storage device among an arbitrarily large number of parallel processes with typically no wasted memory space and continued operations even when an error or interrupt occurs is disclosed. In a networked computer system having a communication network connecting a primary storage device between one or more computer devices and a secondary storage device, when some type of interrupt is generated or an error condition occurs or is otherwise indicated, a transfer of data from primary to secondary storage is indicated. A state indicator having at least a non-backup and a backup state may be set to the backup state to indicate that a data transfer from the primary storage device to the secondary storage device should occur. Alternatively, the transfer from the primary to the secondary storage device can begin without the use of a state indicator.

Abstract: A method and apparatus for storing on centralized mass storage devices archival data from multiple computers in a networked environment. In a networked computer system having a communication network interconnecting one or more computers and a storage unit, parallel processes are created to perform repeated backup operations for disks on computer devices on the communication network. The backup operations for a disk include a backup initialization which occurs when a primary storage device does not have a full index or a backup data file for a disk but a secondary storage device does. During a backup initialization, data from the files and directories on that disk along with an index entry for each file or directory are passed to the primary storage device which directly passes that information directly through to the secondary storage device. The index entries are incorporated into a full index and the data is incorporated into a backup data file.