How do pods in a service discover each other using DNS within a namespace?

How do pods in a service discover each other using DNS within a namespace?

• A. By the service name (DNS: <service-name>)
• B. By the pod IP address
• C. By the Node name
• D. By environment variables

Answer: (A)

Pods discover each other within a namespace by resolving the DNS entry for a Service. Each Service gets a stable DNS name, and that name resolves to the Service’s ClusterIP, allowing requests to be load-balanced to the pods backing the service. You can use the simple form of the name inside the same namespace (serviceName), or the fully qualified name serviceName.namespace.svc.cluster.local if needed. This DNS-based approach is preferred over using pod IPs, which are ephemeral, and over Node names, which aren’t used for inter-pod service discovery. Environment variables may exist for certain startup configurations, but they’re not the primary mechanism for dynamic service discovery.

Pods discover each other within a namespace by resolving the DNS entry for a Service. Each Service gets a stable DNS name, and that name resolves to the Service’s ClusterIP, allowing requests to be load-balanced to the pods backing the service. You can use the simple form of the name inside the same namespace (serviceName), or the fully qualified name serviceName.namespace.svc.cluster.local if needed. This DNS-based approach is preferred over using pod IPs, which are ephemeral, and over Node names, which aren’t used for inter-pod service discovery. Environment variables may exist for certain startup configurations, but they’re not the primary mechanism for dynamic service discovery.