Chapter 9. Fault Tolerance and Reliability

It is never possible to guarantee total reliability and fault tolerance. Hardware failure and human error is inevitable. However, you can ensure that a system will generally tolerate failures, maintain data consistency and make forward progress. Fault-tolerance techniques, such as transactions or replication, always comes at a cost to performance. This trade-off between performance and fault-tolerance is best achieved with knowledge of the application. Attempting to uniformly impose a specific approach to all applications inevitably leads to poorer performance in situations where it was not necessary. As such, you will find that many of the fault-tolerance techniques supported by the JBoss Enterprise SOA Platform are disabled by default. You should enable them only when needed.