Practical Guide to Building a Eureka Service Registry Cluster with Ribbon Load Balancing

The article walks through a hands‑on implementation of a service discovery solution using Netflix Eureka and Spring Cloud, demonstrating how to register services, perform inter‑service calls without hard‑coded IPs, and achieve load balancing with Ribbon.

1. Create Eureka Server – A Spring Boot application annotated with @SpringBootApplication and @EnableEurekaServer is set up. The application.yml configures the server port (8761) and disables self‑registration ( register-with-eureka: false) and registry fetching ( fetch-registry: false). Required Maven dependencies are added for Spring Cloud and Eureka Server.

2. Build Product Service – Two instances run on ports 8006 and 8007. The application.yml registers each instance with the Eureka server ( defaultZone: http://localhost:8761/eureka). A @RestController provides a /product/{name} endpoint returning a simple string. Maven includes spring-boot-starter-web and Eureka client dependencies.

3. Build Order Service – Runs on port 9091, includes Ribbon for client‑side load balancing. The configuration adds spring-cloud-starter-netflix-ribbon. A RestTemplate bean is annotated with @LoadBalanced so calls to http://ProductService/product/{id} are resolved via Eureka. The controller exposes /order/{id} which forwards the request to the product service.

4. Form Eureka Cluster – Two Eureka servers (ports 8761 and 8762) are configured to register with each other via defaultZone URLs, and the local hosts file maps eureka-server1 and eureka-server2 to 127.0.0.1. After starting both, the dashboards at http://localhost:8761/ and http://localhost:8762/ show both servers, confirming clustering.

5. Register Services to the Cluster – Product and order services point their defaultZone to both Eureka instances ( http://localhost:8761/eureka,http://localhost:8762/eureka), enabling high availability.

6. Test the Setup – Using Postman or a browser, invoke the product API ( http://localhost:8006/getProduct/...) and the order API ( http://localhost:9091/order/...). The order service retrieves the product service URL from Eureka and calls it via Ribbon, demonstrating load‑balanced requests across the two product instances.

7. Summary – The tutorial covers how to use Eureka as a registration center, register multiple services, avoid hard‑coded IPs, create a Eureka cluster, and combine it with Ribbon to achieve client‑side load balancing in a microservice architecture.