US 6,292,905 B1 · Method for providing a fault tolerant network using distributed server processes to remap clustered network resources to other servers during server failure

Abstract

The method of the current invention provides a fault tolerant access to a network resource. A replicated network directory database operates in conjunction with server resident processes to remap a network resource in the event of a server failure. The records/objects in the replicated database contain for each network resource, a primary and a secondary server affiliation. Initially, all users access a network resource through the server identified in the replicated database as being the primary server for the network resource. When server resident processes detect a failure of the primary server, the replicated database is updated to reflect the failure of the primary server, and to change the affiliation of the network resource from its primary to its backup server. This remapping occurs transparently to whichever user/client is accessing the network resource. As a result of the remapping, all users access the network resource through the server identified in the replicated database as the backup server for the resource. When the server resident processes detect a return to service of the primary server, the replicated database is again updated to reflect the resumed operation of the primary server. This remapping of network resource affiliations also occurs transparently to whichever user/client is accessing the network resource, and returns the resource to its original fault tolerant state.

Claims28

Dependent claims

A method for fault tolerant access to a network resource, on a network with a client workstation and a first and a second server, said method for fault tolerant access comprising the acts of:

selecting a first server to provide communications between a client workstation and a network resource;
detecting a failure of the first server, comprising the acts of:
monitoring across a common bus, at a second server, communications between the first server and the network resource across the common bus by noting a continual change in state of the network resource, and
observing a termination in the communications between the first server and the network resource across the common bus by noting a stop in the continual change in state of the network resource;
and
routing communications between the client workstation and the network resource via the second server.

3 more elements

A program storage device encoding instructions for:

causing a computer to provide a network resource database, the database including individual records corresponding to network resources, and the network resource database including a first record corresponding to the network resource and the first record identifying a primary server for the network resource as a first server;
causing a computer to select, on the basis of the first record, the first server to provide communications between a client workstation and the network resource;
causing a computer to recognize the backup server for the network resource as the second server;
causing a computer to detect a failure of the first server, including:
causing a computer to monitor across a common bus, at the second server, communications between the first server and the network resource across the common bus by noting a continual change in state of the network resource, and
causing a computer to observe a termination in the communications between the first server and the network resource across the common bus by noting a stop in the continual change in state of the network resource;
and
causing a computer to route communications between the client workstation and the network resource via the second server, responsive to said recognizing and detecting acts.

5 more elements

A method for providing fault tolerant access to a network resource, on a network with a client workstation and a first and a second server and a network resource database, wherein the network resource database includes a first record corresponding to a network resource and the first record includes a first field containing the name of the network resource and a second field containing the host server affiliation of the network resource;

said method for fault tolerant access comprising the acts of:
expanding the network resource database to include a third field for naming the primary server affiliation for the network resource and a fourth field for naming the backup server affiliation for the network resource;
naming the first server in the third field;
selecting, on the basis of the first record, the first server to provide communications between the client workstation and the network resource;
naming the second server in the fourth field;
recognizing, on the basis of the fourth field of the first record, the backup server for the network resource as the second server;
detecting a failure of the first server, including the acts of:
monitoring across a common bus, at the second server, communications between the first server and the network resource across the common bus by noting a continual change in state of the network resource, and
observing a termination in the communications between the first server and the network resource across the common bus by noting a stop in the continual change in state of the network resource;
and
routing communications between the client workstation and the network resource via the second server, responsive to said recognizing and detecting acts.

8 more elements

A computer usable medium having computer readable program code means embodied therein for causing fault tolerant access to a network resource on a network with a client workstation and a first and second server, and a network resource database, wherein the network resource database includes a first record corresponding to a network resource and the first record includes a first field containing the name of the network resource and a second field containing the host server affiliation of the network resource;

the computer readable program code means in said article of manufacture comprising;
computer readable program code means for causing a computer to expand the network resource database to include a third field for naming the primary server affiliation for the network resource and a fourth field for naming the backup server affiliation for the network resource;
computer readable program code means for causing a computer to name the first server in the third field;
computer readable program code means for causing a computer to select, on the basis of the first record, the first server to provide communications between the client workstation and the network resource;
computer readable program code means for causing a computer to name the second server in the fourth field;
computer readable program code means for causing a computer to recognize, on the basis of the fourth field of the first record, the backup server for the network resource as the second server;
computer readable program code means for monitoring across a common bus, at a second server, communications between the first server and the network resource across the common bus by noting a continual change in state of the network resource, and observing a termination in the communications between the first server and the network resource across the common bus by noting a stop in the continual change in state of the network resource;
and
computer readable program code means for causing a computer to route communications between the client workstation and the network resource via the second server, responsive to said recognizing and detecting acts.

6 more elements

Dependencies are inferred from the claim text.

Method for providing a fault tolerant network using distributed server processes to remap clustered network resources to other servers during server failure

Life of this patent

Method for providing a fault tolerant network using distributed server processes to remap clustered network resources to other servers during server failure

Life of this patent

Abstract

Claims28