Design approaches for real-time transaction processing remote site recovery

Computer applications are evolving to the point where failure to provide service is unacceptable. A class of failure receiving more and more attention is site failure, whether it be due to disaster or planned outage. The design approaches to implementing real-time site recovery for transaction processing/database systems are examined. Several approaches are described, along with the appeal and problems of each approach. In remote logging, system log data are transported to the remote site where they are used, as appropriate, to reconstruct the active site´s system. The most flexible approach to transport is sending data as they are created, using communications facilities. The IBM Almaden Research Center started the Lifeboat project in order to understand real-time remote site recovery technology. After design approaches were evaluated the remote logging approach was chosen for further investigation. The Lifeboat project for remote site recovery is briefly discussed, along with some of the challenges it faces.<>