Essential cluster services
Now that we’ve covered the architecture of both the control plane and the worker nodes, we need to explore the services that allow them—and the applications they run—to function as a cohesive system. These essential services handle critical tasks like networking and service discovery, tying all the individual components together.
Service discovery with DNS
For services to find each other within a Kubernetes cluster, they need a reliable discovery mechanism. This is the critical role of DNS. While not a core compiled component of the control plane itself, DNS is an essential cluster service, typically running as Pods (like CoreDNS), that enables reliable communication between applications.
Here’s how the DNS service fits within the Kubernetes control plane:
- Kubernetes control plane components: The Kubernetes control plane comprises several critical components, such as the API server, etcd, the controller...
