StatefulSet Kubernetes | Understand what StatefulSet in Kubernetes is and how it works

In this Kubernetes StatefulSet tutorial, I explain the difference between Deployment and StatefulSet.
I also show you how to deploy databases using StatefulSet component.

Kubernetes StatefulSets are used to deploy specifically stateful applications. In order to understand how StatefulSet works, you first need to understand how database clusters work, as well concepts of Kubernets StatefulSet vs Deployment.

While StatefulSet is used for stateful applications, Deployment component is used to deploy stateless applications. So the question is: what is the difference between Deployment and StatefulSet components?

Pods deployed by Deployment are identical and interchangeable, created in random order with random hashes in their Pod names.
In contrast to that, the Pods deployed by StatefulSet component are NOT identical. They each have their own sticky identity, which they keep between restarts and each can be addressed individually. Thus, they can’t be created or deleted at the same time or in any order.

How these identities are created and why its so important, I explain in detail in this video.

▬▬▬▬▬▬ T I M E S T A M P S

• 0:00 - Intro
• 0:07 - What is StatefulSet? Difference of stateless and stateful applications
• 1:57 - Deployment of stateful and stateless applications
• 3:42 - Deployment vs StatefulSet
• 5:40 - Pod Identity
• 6:14 - Scaling database applications: Master and Slave Pods
• 10:15 - Pod state
• 11:40 - Pod Identifier
• 13:17 - 2 Pod endpoints
• 14:27 - Final note - replicating stateful apps
• 15:26 - What we covered and what to learn next

#kubernetes #deveops