Asynchronously shadowing record updates in a remote copy session using track arrays
US5720029A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1995 |
| Grant date | Feb 17, 1998 |
| Priority date | — |
| Expiry date | Jul 25, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/2064
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A disaster recovery system providing asynchronous remote data shadowing between a primary and a secondary site uses a pair of track arrays for each primary data storage device of a remote copy pair to monitor which record updates are in transit between the primary site and the secondary site. A host processor at the primary site of the disaster recovery system transfers a sequentially consistent order of copies of record updates to the secondary site for back-up purposes. The copied record updates are stored on the secondary data storage devices which form remote copy pairs with the primary data storage devices at the primary site. One track array, the active track array, is used to set elements according to which tracks on the primary data storage device receive record updates from the host processor at the primary site. The other track array, the recovery track array, designates which record updates comprise the copied record updates currently transferred from the primary site to the secondary site for data shadowing and is used for recovery should an error interrupt the transfer. The track arrays are toggled once the consistency group transfer completes, the recovery track array…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.