What are finalizers in Kubernetes and how do they work?

What are finalizers in Kubernetes and how do they work?

Finalizers are special metadata in Kubernetes that allow you to control the deletion of resources. They ensure that certain cleanup actions are completed before a resource is fully deleted.

Can you give me an example of how to use finalizers?

Sure! For instance, if you have a custom resource that needs to perform some cleanup tasks before deletion, you can add a finalizer to it. When the resource is deleted, Kubernetes will call your cleanup logic before actually removing the resource.

What happens if the finalizer doesn't complete?

If the finalizer doesn't complete, the resource will remain in a 'terminating' state. This means it won't be fully deleted until the finalizer logic is successfully executed.

Are there any best practices for using finalizers?

Yes, it's important to ensure that your finalizer logic is idempotent and can handle failures gracefully. Also, make sure to remove the finalizer once the cleanup is done to avoid resource leaks.