Endpoints and endpoint slices in Kubernetes - Commands & Configuration

Introduction

When you run applications in Kubernetes, you often need to connect services to the right pods. Endpoints and endpoint slices help Kubernetes keep track of which pods belong to a service, so traffic goes to the right places.

When you want to see which pods are connected to a service in your cluster.

When you need to debug why a service is not routing traffic correctly.

When you want to understand how Kubernetes manages network connections between services and pods.

When you want to optimize network performance by using endpoint slices for large services.

When you want to monitor or troubleshoot service discovery in your Kubernetes cluster.

Commands

This command lists all the endpoints in the current namespace. Endpoints show which pods are linked to each service.

Terminal

kubectl get endpoints

Expected Output

NAME           ENDPOINTS           AGE

kubernetes     10.96.0.1:443       10d

This command lists all endpoint slices in the current namespace. Endpoint slices are a newer, scalable way to track service endpoints.

Terminal

kubectl get endpointslices

Expected Output

NAME                         ADDRESSTYPE   PORTS   ENDPOINTS   AGE

kubernetes-abc123             IPv4          443     10.96.0.1   10d

This command shows detailed information about the endpoints for the 'kubernetes' service, including the IP addresses and ports of pods.

Terminal

kubectl describe endpoints kubernetes

Expected Output

Name:         kubernetes

Namespace:    default

Endpoints:    10.96.0.1:443

Age:          10d

This command shows detailed information about a specific endpoint slice, including addresses and ports it covers.

Terminal

kubectl describe endpointslice kubernetes-abc123

Expected Output

Name:         kubernetes-abc123

Namespace:    default

AddressType:  IPv4

Ports:

  Name:       https

  Port:       443

Endpoints:

  10.96.0.1

Age:          10d

Key Concept

Endpoints and endpoint slices map services to the pods that serve them, enabling Kubernetes to route traffic correctly.

Common Mistakes

Trying to edit endpoints directly to change service pods.

Endpoints are managed automatically by Kubernetes and manual edits will be overwritten.

Change the service selector or pod labels to update which pods belong to a service.

Ignoring endpoint slices and only using endpoints for large services.

Endpoints can become inefficient and slow with many pods; endpoint slices scale better.

Use endpoint slices for services with many pods to improve performance.

Summary

Use 'kubectl get endpoints' to see which pods are linked to services.

Use 'kubectl get endpointslices' to view scalable endpoint information.

Describe endpoints or endpoint slices to get detailed pod IPs and ports.