What is the default Kubernetes service that establishes a service with an internal IP address reachable only within the cluster?

What is the default Kubernetes service that establishes a service with an internal IP address reachable only within the cluster?

• A. NodePort
• B. ExternalName
• C. ClusterIP
• D. LoadBalancer

Answer: (C)

ClusterIP is the internal-facing service type that gives you a virtual IP inside the cluster’s service network. This IP is reachable only from pods within the cluster, and the service is usually accessed by its DNS name (for example, a service name in the cluster’s DNS, like my-service.namespace.svc.cluster.local). If you don’t specify a type, Kubernetes defaults to ClusterIP, so the service remains internal by design. Other types expose the service externally: NodePort opens a port on each node, LoadBalancer provisions an external load balancer, and ExternalName maps to an external DNS name. So the default internal, cluster-only reachable service is ClusterIP.

ClusterIP is the internal-facing service type that gives you a virtual IP inside the cluster’s service network. This IP is reachable only from pods within the cluster, and the service is usually accessed by its DNS name (for example, a service name in the cluster’s DNS, like my-service.namespace.svc.cluster.local). If you don’t specify a type, Kubernetes defaults to ClusterIP, so the service remains internal by design. Other types expose the service externally: NodePort opens a port on each node, LoadBalancer provisions an external load balancer, and ExternalName maps to an external DNS name. So the default internal, cluster-only reachable service is ClusterIP.