Patent · US Expired

Switching control in a fault tolerant system

US5822512A · kind A · utility

106Cited by
21References
50Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 5, 1996
Grant dateOct 13, 1998
Priority date
Expiry dateJun 5, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F11/22
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Control is switched from a first server to a second server in a fault tolerant system. The first and second servers are coupled with an expansion bus in an expansion box for communication with the expansion bus. An indication is provided to the second server to indicate the activity state of the first server. Communication between the first server and the expansion box is disabled if the indication indicates the first server is inactive. Communication between the second server and the expansion bus is disabled if the indication indicates that the first server is active. Communication between the second server is enabled if the indication indicates that the first server is inactive. The indication includes a heartbeat message transmitted periodically to the second server. The expansion bus includes a PCI bus.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.