Headless Service with StatefulSets role.

Headless Service with StatefulSets role.

• A. Provides stable DNS names for pods
• B. Creates external IP
• C. Exposes pods outside cluster
• D. Balances traffic

Answer: (A)

The essential idea is that a headless service with a StatefulSet gives each pod a stable, discoverable identity inside the cluster. When you create a headless service (clusterIP: None) for a StatefulSet, Kubernetes does not assign a single IP for the whole service. Instead, it creates DNS records for each pod, so you can reach each pod directly by a predictable name such as statefulset-name-ordinal.service-name.namespace.svc.cluster.local. This stability in the pod’s DNS name (tied to the ordinal index) is what stateful workloads like databases rely on for clustering and replication, even as the underlying Pod IPs may change on rescheduling. Because there’s no single cluster IP, this setup doesn’t provide a single endpoint to balance traffic to all pods. External exposure or general load balancing across pods isn’t the goal here; instead, you get direct, stable addresses per pod and let the application or client handle addressing and load balancing as needed.

The essential idea is that a headless service with a StatefulSet gives each pod a stable, discoverable identity inside the cluster. When you create a headless service (clusterIP: None) for a StatefulSet, Kubernetes does not assign a single IP for the whole service. Instead, it creates DNS records for each pod, so you can reach each pod directly by a predictable name such as statefulset-name-ordinal.service-name.namespace.svc.cluster.local. This stability in the pod’s DNS name (tied to the ordinal index) is what stateful workloads like databases rely on for clustering and replication, even as the underlying Pod IPs may change on rescheduling.

Because there’s no single cluster IP, this setup doesn’t provide a single endpoint to balance traffic to all pods. External exposure or general load balancing across pods isn’t the goal here; instead, you get direct, stable addresses per pod and let the application or client handle addressing and load balancing as needed.