« PreviousContinue »
United States Patent t^j
Kenley et al.
[i i] Patent Number:  Date of Patent:
Muuss et al., "Bump The BRL/USNA Migration
Project", Mar. 5, 1989, pp. 1-19.
Thompson et al., "The Operation and Use of a 2 Tera-
byte Optical Archival Store", Digest of Papers, Ninth
IEEE Symposium, Nov., 1988, pp. 88-92.
Arneson, D. A., "Mass Storage Archiving in Network
Environments", Digest of Papers, IEEE Symposium,
Oct.-Nov. 1988, pp. 45-50.
Hume, A., "The File Motel—An Incremental Backup
System for Unix", Summer USENIX '88, pp. 61-72.
Arnold et al., "Automatic UNIX Backup in a Mass
Storage Environment", Proceed, of USENIX Assoc.,
Feb. 1988, pp. 131-136.
Christman, "Experience With File Migration", Los Alamos National Lab report No. LA-9014, Oct. 1981. McLarty et al., "A Functional View Of The Los Alamos Central File System", Sixth IEEE Symposium, Jun. 1984, pp. 10-16.
Collins et al., "A Network File Storage System", Fifth IEEE Symposium, Oct. 1982, pp. 99-102.
(List continued on next page.)
Primary Examiner—Paul V. Kulik
Attorney, Agent, or Firm—Lahive & Cockfield
A digital data storage apparatus has primary, secondary and backing storage elements characterized by respectively longer access times. A level detector signals when the quantity of data in the secondary store exceeds a threshold amount. A data migrator responds by moving selected data files from the secondary store to the backing store. The apparatus also includes a baseline back-up element that stores archive copies of a set of selected data files. A full back-up element stores archive copies of those files that, (1) were originally copied to the baseline back-up set but have since changed, or (2) are not otherwise within the baseline back-up set. For those files which were originally copied to the baseline back-up set and which have not changed, the full backup element stores pointers indicating locations of the respective files in the baseline back-up set.
35 Claims, 5 Drawing Sheets
mmii ,-,—1 I-'* lire. ''. '■■
Gwatking, Electronics Research Lab Adelaide (Austra-
lia), Report No. ERL-0009-TR, Apr. 1978.
Miller, "Direct Access Data Migration System", U.S.-
D.A. Report No. USDA/DF-78/016, Mar. 1978.
Johnson, C, "IBM 3850—Mass Storage System",
AFIPS Conference Proceedings, May 1975, vol. 44, pp.
Johnson, C, "The IBM 3850: A Mass Storage System
with Disk Characteristics", Proc of the IEEE, vol. 63,
No. 8, Aug. 1975, pp. 1166-1170.
Murray, "Document Based on Clustered Files", Thesis,
Cornell Univ. Dept. of Computer Science, Ithaca, NY,
Fiedler, "QBAX: An Incremental Backup Utility",
Microsystems USA, vol. 4, No. 10, Oct. 1983, p. 84.
McGee, "Epoch Combines Magnetic Optical Drives",
Computer Systems News, Oct. 31, 1988.
Epoch Systems press release, "Epoch Systems To De-
velop New Generation of High Capacity File Servers
For Networked Workstations", Mar. 14, 1988.
Epoch Systems "Order Acknowledgement," Dec. 16,
1988, Epoch Systems Inc.
Epoch Systems "Invoice," Dec. 16, 1988, Epoch Systems Inc.
GTE Directories Service Corporation "Invoice," Dec. 16, 1988.
Edward Mendelson, "Backup Software For the Moment After", PC Magazine, Aug. 1989, pp. 269-319. "Tape Backup Measuring Speed & Cost Per Megabyte", PC Magazine, Feb. 11, 1986, pp. 106-132.