Book Image

The KCNA Book

By : Nigel Poulton
Book Image

The KCNA Book

By: Nigel Poulton

Overview of this book

There is a huge benefit in building small, specialized, single-purpose apps that can self-heal, auto scale, and update regularly without needing downtime. Kubernetes and cloud-native technologies come in handy in building such apps. Possessing the knowledge and skills to leverage Kubernetes can positively enhance possibilities in favor of architects who specialize in cloud-native microservices applications. ‘The KCNA Book’ is designed to help those working in technology with a passion to become certified in the Kubernetes and Cloud-Native Associate Exam. You will learn about containerization, microservices, and cloud-native architecture. You will learn about Kubernetes fundamentals and container orchestration. The book also sheds light on cloud-native application delivery and observability. It focuses on the KCNA exam domains and competencies, which can be applied to the sample test included in the book. Put your knowledge to the test and enhance your skills with the all-encompassing topic coverage. Upon completion, you will begin your journey to get the best roles, projects, and organizations with this exam-oriented book.
Table of Contents (12 chapters)
9
8: Sample test
Appendix B: Sample Test answers

The Kubernetes API and API server

If you’re new to the concept of APIs, you should think of the Kubernetes API as a catalog listing every possible Kubernetes object and their properties. This catalog (API) is accessed via the API server.

For example, Kubernetes defines a lot of objects such as pods, deployments, replicasets, statefulsets, cronjobs, services, ingresses, network policies, and more. All of these are defined in the API, along with all of their properties that can be used to configure them. When you deploy an object, such as a deployment, you define it in a declarative manifest that you send to the API server where it’s authenticated, authorised, and scheduled to the cluster.

If you try to deploy an object that isn’t defined in the API, the operation will fail. Also, if you try and configure a property of an object that no longer exists, it will fail.

The Kubernetes API is divided into named groups to make it easier to understand, navigate, and expand...