CKAD Scenarios about Admission Controllers and Api Deprecations
Scenarios according to the 2021 updated CKAD about Admission Controllers and Api Deprecations
FREE CKAD Scenarios? YES!
(we also already have CKA and CKS ones)
killercoda.com/killer-shell-ckad
This week’s scenarios
This week we added these scenarios:
Admission Controllers
In this scenario we learn how to list, enable and disable Admission Controller Plugins. We also see what Admission Controllers can do and control.
Admission Control modules are software modules that can modify or reject requests. In addition to the attributes available to Authorization modules, Admission Control modules can access the contents of the object that is being created or modified. (source)
Admission Controllers can reject certain resource definitions (like a Deployment with less than 2 replicas) or they can even change/mutate resources (like always adding certain labels to Pods).
Installing Admission Controller Plugins is more of a task for administrators, but for application developers it’s still important to understand this in detail.
Api Deprecations
In this scenario we learn about Api Versions, Groups and Deprecations.
Kubernetes is under constant heavy development, which means things change all the time. But these won’t change from one version to another, for example from 1.23 to 1.24 , people are given more time to convert.
If for example the definition of CronJob changes, then it’ll be done first under a different Api Version, like batch/v1beta1. The old version and new version will coexist for some time. Then after public feedback and over time, the changes will be released under for example batch/v1.
Here you can see an overview over current deprecations.
As an application developer on top of K8s it’s important to understand which versions you should use and also how to update the resources of your applications.
