DNS

An internal DNS server is optional and can be installed as an add-on, but it is highly recommended in standard deployments as it simplifies service discovery and networking. Currently, the default DNS server used by Kubernetes is CoreDNS (https://coredns.io/).

Kubernetes automatically adds an internal static IP address of the DNS server to the domain name resolution configuration for each container. This means that processes running in Pods can communicate with Services and Pods running in the cluster just by knowing their domain name, which will be resolved to the actual internal IP address. The concept of Kubernetes Service objects will be covered in the next section.

Now, let's take a look at the most commonly used Kubernetes objects.