Book Image

Kubernetes for Developers

By : Joseph Heck
Book Image

Kubernetes for Developers

By: Joseph Heck

Overview of this book

Kubernetes is documented and typically approached from the perspective of someone running software that has already been built. Kubernetes may also be used to enhance the development process, enabling more consistent testing and analysis of code to help developers verify not only its correctness, but also its efficiency. This book introduces key Kubernetes concepts, coupled with examples of how to deploy and use them with a bit of Node.js and Python example code, so that you can quickly replicate and use that knowledge. You will begin by setting up Kubernetes to help you develop and package your code. We walk you through the setup and installation process before working with Kubernetes in the development environment. We then delve into concepts such as automating your build process, autonomic computing, debugging, and integration testing. This book covers all the concepts required for a developer to work with Kubernetes. By the end of this book, you will be in a position to use Kubernetes in development ecosystems.
Table of Contents (16 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Stateful Sets


Following dynamic provisioning, as you think about persistence systems – whether they are classic databases, key-value data stores, memory caches, or document-based datastores – it is common to want to have some manner of redundancy and failover. ReplicaSets and deployments go a fairly significant way to supporting some of that capability, especially with persistent volumes, but it would be greatly beneficial to these systems to have them more fully integrated with Kubernetes, so that we can leverage Kubernetes to handle the life cycle and coordination of these systems. A starting point for this effort is Stateful Sets, which act similarly to a deployment and ReplicaSet in that they manage a group of pods.

Stateful Sets differ from the other systems as they also support each pod having a stable, unique identity and specific ordered scaling, both up and down. Stateful Sets are relatively new in Kubernetes, first appearing in Kubernetes 1.5, and moving into beta in version 1.9...