The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 16, 2013
Filed:
Jan. 31, 2011
Stephen John Vivian, Londonderry, NH (US);
George H. Claborn, Amherst, NH (US);
Mahesh Baburao Girkar, Cupertino, CA (US);
Vinay H. Srihari, South San Francisco, CA (US);
Steve Taihung Lee, Hollis, NH (US);
Stephen John Vivian, Londonderry, NH (US);
George H. Claborn, Amherst, NH (US);
Mahesh Baburao Girkar, Cupertino, CA (US);
Vinay H. Srihari, South San Francisco, CA (US);
Steve Taihung Lee, Hollis, NH (US);
Oracle International Corporation, Redwood Shores, CA (US);
Abstract
Techniques used in an automatic failover configuration having a primary database system, a standby database system, and an observer. In the automatic failover configuration, the primary database system remains available even in the absence of both the standby and the observer as long as the standby and the observer become absent sequentially. The failover configuration may use asynchronous transfer modes to transfer redo to the standby and permits automatic failover only when the observer is present and the failover will not result in data loss due to the asynchronous transfer mode beyond a specified maximum. The database systems and the observer have copies of failover configuration state and the techniques include techniques for propagating the most recent version of the state among the databases and the observer and techniques for using carefully-ordered writes to ensure that state changes are propagated in a fashion which prevents divergence.