System for migrating data by selecting a first or second transfer means based on the status of a data element map initialized to a predetermined state
US5680640A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1995 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Sep 1, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0866
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and method for providing on-line, real-time, transparent data migration from a first data storage system to a second data storage system. The first data storage system which had previously been coupled to a host, network or other data processing system is disconnected from the host and connected to a second data storage system. The second data storage system is coupled to the host or data processing system. The second data processing system includes a data map or table which indicates which data elements are stored on the second data storage system and which corresponding data elements on the first data processing device have been copied to the second data storage system. When the host, network or data processing system requests data from a data storage system, the second data storage system determines whether or not the data is stored on the second or first data storage system. If the data is stored on the second data storage system, the data is made available to the requesting device. If the data is not stored on a second data storage system, the second data storage system issues a request to the first data storage system, retrieves the data, makes the data available to …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.