Servicenamespacesvcclusterlocal

Servicenamespacesvcclusterlocal is a term that highlights the DNS naming convention used by Kubernetes for internal service addresses. It refers to the sequence of labels that form the fully qualified domain name (FQDN) used to reach a service from within the cluster: service, namespace, svc, cluster, local.

In Kubernetes, the canonical FQDN for a service is structured as <service>.<namespace>.svc.cluster.local. Each label in this sequence has a role: the first label is the service name, the second is the Kubernetes namespace where the service resides, the third label (svc) indicates a Kubernetes service, followed by the cluster domain (cluster) and the top-level domain (local). This naming enables predictable, cluster-internal service discovery without requiring IPs that may change as pods scale.

Example: a service named frontend in the default namespace would be frontend.default.svc.cluster.local. Pods within the cluster can resolve this name to the service’s cluster IP using the cluster’s DNS service (CoreDNS or kube-dns).

DNS resolution and configuration: Kubernetes runs a DNS addon that provides resolution for these names. The default cluster domain is cluster.local, but the exact suffix can be customized during cluster setup. The internal service domain is primarily for intra-cluster communication; external clients typically access services via NodePort, LoadBalancer, or Ingress, rather than the internal FQDN.

See also: Kubernetes DNS, Kubernetes Service, Namespace.