What does DNS provide inside Kubernetes?

In Kubernetes, DNS provides automatic resolution of service and pod names within the cluster. This allows cluster components to communicate with each other using friendly names rather than IP addresses, which can change.

Main functions of DNS in Kubernetes:

• Service name resolution: each service gets a DNS name, for example my-service.namespace.svc.cluster.local, which can be used to access the service.
• Ensuring address stability: Pod IP addresses are dynamic, but DNS names are constant, simplifying interaction.
• Support for Headless services: DNS returns a list of pod IPs, allowing clients to connect directly to them.

Typically, CoreDNS or kube-dns is used in the cluster, which automatically updates records when changes occur in the cluster.