Highly available database clusters that move client connections between hosts

Abstract

Aspects of embodiments of the present disclosure include a highly available database cluster that can maintain a connection with potentially geographically remote client application programs, including non-fault tolerant application programs, even in the event of one of the database management systems (DBMS) of the cluster becoming unavailable. For example, the database cluster can advantageously move a client connection between a failing, unbalanced, or overloaded DBMS, to another DBMS within the cluster. The database cluster can include connection managers that monitor a connection between a client application program and a primary DBMS. When one connection manager determines that the primary DBMS is unavailable, the connection manager of a secondary DBMS can assume the connection to the client application as if it were the primary DBMS. The connection manager can finish all open transactions, thereby avoiding the need to roll back the same. Moreover, the connection managers can monitor the connection at the DBMS communication level, such as, for example, the SQL*Net level.

Description

REFERENCE TO RELATED APPLICATION[0001] The present application claims priority benefit under 35 U.S.C. .sctn.119(e) from U.S. Provisional Application No. 60 / 266,908, filed Feb. 6, 2001, entitled "HIGHLY AVAILABLE DATABASE CLUSTERS," which is incorporated herein by reference.FIELD OF THE INVENTION[0002] The present invention relates to the field of highly available database clusters. More specifically, the invention relates to database clusters that transparently move client connections between hosts.BACKGROUND OF THE INVENTION[0003] A database is generally considered to be a collection of information or data organized in a way that computer programs can quickly access or select desired portions of the collection. A database management system (DBMS) includes the collection of computer programs that enable the quick storage, selection, modification, and extraction of desired portions of data from the database. Exemplary DBMSs include those commercially available from Oracle Corporatio...

AI Technical Summary

Benefits of technology

0009] Therefore, a need exists for a database cluster that can maintain a connection with potentially geographically remote client application programs, including non-fault tolerant application programs, even in the event of a failure or other unavailability of the primary DBMS. Accordingly, aspects of embodiments of the present disclosure include a highly available database cluster that can maintain a connection with potentially geographically remote client application programs, including non-fault tolerant application programs. For example, the database cluster can advantageously move a client connection between a failing, unbalanced ,or overloaded DBMS, to another DBMS within the database cluster.

Problems solved by technology

When one connection manager determines that the primary DBMS is unavailable, has an unbalanced share of the workload of the cluster, or the like, the connection manager of a secondary DBMS can assume the connection to the client application as if it were the primary DBMS.

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