# StatefulSets

TIP

During this tutorial you'll learn how to manage StatefulSets on Kubernetes.

  • Level: beginner
  • Requirements: none
  • Previous Tutorials: pods
  • Can run on Cluster: any
  • Can run on Namespace: any
  • Images used: nginx:alpine, nginx:1.19.2-alpine

StatefulSets(opens new window) manages stateful applications.

# Nginx

  • Create StatefulSet
    • Name: nginx
    • Image: nginx:alpine

Let's run a simple StatefulSet with image nginx:alpine which runs an nginx(opens new window) web server. Once the StatefulSet is created it will manage one running Pod. We can scale up the StatefulSet to get more instances. Unlike Deployment, the Pods created have now fixed names (i.e. nginx-0 and nginx-1) that ensure stable and unique network identifiers. When a Pod is down, a fresh pod with the same name will be recreated in it's place.

Nginx Deployment

# Update Version

Let's update the image of the StatefulSet to nginx:1.19.2-alpine. This will trigger an ordered rolling update.

Nginx StatefulSet Update version

# Cleanup

Remember to delete the following resources after you finish this tutorial:

  • on active namespace:
    • statefulsets/nginx