Remote data mirroring
US6173377A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1998 |
| Grant date | Jan 9, 2001 |
| Priority date | — |
| Expiry date | Apr 17, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99942
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Two data storage systems are interconnected by a data link for remote mirroring of data. Each volume of data is configured as local, primary in a remotely mirrored volume pair, or secondary in a remotely mirrored volume pair. Normally, a host computer directly accesses either a local or a primary volume, and data written to a primary volume is automatically sent over the link to a corresponding secondary volume. Each remotely mirrored volume pair can operate in a selected synchronization mode including synchronous, semi-synchronous, adaptive copy-remote write pending, and adaptive copy-disk. Direct write access to a secondary volume is denied if a "sync required" attribute is set for the volume and the volume is not synchronized. If a "volume domino" mode is enabled for a remotely mirrored volume pair, access to a volume of the pair is denied when the other volume is inaccessible. In a "links domino" mode, access to all remotely mirrored volumes is denied when remote mirroring is disrupted by an all-links failure. The domino modes can be used to initiate application-based recovery, for example, recovering a secondary data file using a secondary log file. In an active migration mode…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.