Name two service discovery which you have implemented in your spring boot microservice application? Is there any configuration needs to be added to your application or in K8s cluster related to this?

Question

Accepted Answer

Service discovery tools let microservices register themselves and locate other services dynamically at runtime instead of relying on hard-coded network addresses; Eureka and Consul are two commonly implemented options in the Spring Boot ecosystem.

Key Points:
• Eureka requires adding the spring-cloud-starter-netflix-eureka-client dependency and configuring eureka.client.service-url.defaultZone to point to the Eureka server so the service can register itself on startup.
• Consul, from HashiCorp, is configured similarly via spring-cloud-starter-consul-discovery and typically runs a Consul agent alongside each application instance or node.
• In a Kubernetes cluster, Consul agents are often deployed as a DaemonSet so every node has a local agent handling registration and health checks.
• Kubernetes itself provides built-in service discovery via DNS and Services/Endpoints objects, which can reduce or eliminate the need for Eureka when running natively on K8s.
• Both tools require health-check configuration so unhealthy instances are removed from the registry automatically.

Example:
A Spring Boot service deployed to Kubernetes with Consul would run a Consul agent as a sidecar or node-level DaemonSet, register itself with a health-check endpoint, and other services would query Consul's catalog API to resolve the current healthy instances.

Code Example:
```
# application.yml (Eureka client)
eureka:
  client:
    service-url:
      defaultZone: http://eureka-server:8761/eureka/
  instance:
    prefer-ip-address: true
```

Interview Tip:
A concise interview answer is:

"I've implemented both Eureka and Consul for service discovery. Eureka just needs the client dependency and a defaultZone pointing at the Eureka server, while Consul additionally requires an agent running per node, which in Kubernetes is usually deployed as a DaemonSet alongside health-check configuration for both."