MP Fault Tolerance provides a simple and flexible solution to build fault-tolerant microservices. Fault tolerance leverages different strategies to guide the execution and result of logic. As stated in the MicroProfile website, retry policies, bulkheads, and circuit breakers are popular concepts in this area. They dictate whether and when executions take place, and fallbacks offer an alternative result when an execution does not complete successfully.

The application that you will be working with is an inventory service, which collects, stores, and returns the system properties. It uses the system service to retrieve the system properties for a particular host. You will add fault tolerance to the inventory service so that it reacts accordingly when the system service is unavailable.

You will use the @Fallback annotations from the MicroProfile Fault Tolerance specification to define criteria for when to provide an alternative solution for a failed execution.

You will also see the application metrics for the fault tolerance methods that are automatically enabled when you add the MicroProfile Metrics feature to the server.