Patent
1996-06-05
1998-10-13
DeCady, Albert
39518501, G06F 1134
Patent
active
058225129
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.
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U.S. Ser. No. 08/491738, Jun. 1995.
Cook M. Damian
Cox B. Tod
Goodrum Alan L.
Miller Joseph P.
Sanders Michael C.
Compaq Computer Corporartion
De'cady Albert
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