This blog post explains how a simple Java application can communicate with a database using service discovery in the DC/OS environment. It highlights the importance of service discovery in multi-container applications, which consist of various components like application servers and databases that may have multiple replicas running as containers. Since containers can be ephemeral and get reassigned different IP addresses when rescheduled, service discovery assigns logical names to components, allowing applications to interact with services by name rather than IP address. The blog demonstrates setting up a DC/OS cluster and using the Marathon framework to define and deploy a Java EE application with a WildFly server and Couchbase database, illustrating the configuration for service discovery and load balancing. The post provides a step-by-step guide on deploying the application using the dcos-maven-plugin and shares the complete source code at a GitHub repository, emphasizing the dynamic and scalable nature of service discovery in container orchestration frameworks.