Complete Guide to Kubernetes Services with Examples

Kubernetes workloads are dynamic, with Pods being created, destroyed, or rescheduled across nodes due to scaling operations or hardware failure. This makes maintaining stable network identities and seamless communication between components challenging. Kubernetes services help abstract a set of endpoints (typically Pods) and provide a way to access those over the network. Services abstract away the complexities of discovery and load balancing, allowing developers to focus on application logic rather than infrastructure. Kubernetes provides four main categories of services: ExternalName, LoadBalancer, NodePort, and ClusterIP (with a subtype of Headless service). The appropriate service type should be chosen based on the use case. For example, if a service only receives internal traffic, there is no reason to pay the additional overhead of NodePort or LoadBalancer services. It's important to monitor the traffic and health of the applications behind a service constantly. Tools like Grafana Kubernetes Dashboard or Prometheus can be used for this purpose. As the system grows, so does the complexity of the infrastructure. Ideally, service objects should live together in the same namespace as the application and be managed in tandem using tools like Argo, Helm, or others. At a certain point, the requirements for the application might become too complex to support via the existing service object functionality. Instead of trying to shoehorn the solution, consider alternatives like Ingress, Service Mesh, or Gateway APIs.