The network service is an application that receives requests and provides a solution. Clients access the service by a network connection. They don't have to know the architecture of the service or how it runs. The only thing that clients have to verify is whether the endpoint of the service can be accessed, and then follow its usage policy to get the response of the server. The Kubernetes Service has similar ideas. It is not necessary to understand every Pod before reaching their functionalities. For components outside the Kubernetes system, they just access the Kubernetes Service with an exposed network port to communicate with running Pods. It is not necessary to be aware of the containers' IPs and ports. Behind Kubernetes Services, we can fulfill a zero-downtime update for our container programs without struggling:
Kubernetes Service-covered Pods by labels of Pods and their selectors
The preceding diagram shows the basic structure of the Service and realizes the following...