Book Image

Mastering Kubernetes - Second Edition

By : Gigi Sayfan
Book Image

Mastering Kubernetes - Second Edition

By: Gigi Sayfan

Overview of this book

Kubernetes is an open source system that is used to automate the deployment, scaling, and management of containerized applications. If you are running more containers or want automated management of your containers, you need Kubernetes at your disposal. To put things into perspective, Mastering Kubernetes walks you through the advanced management of Kubernetes clusters. To start with, you will learn the fundamentals of both Kubernetes architecture and Kubernetes design in detail. You will discover how to run complex stateful microservices on Kubernetes including advanced features such as horizontal pod autoscaling, rolling updates, resource quotas, and persistent storage backend. Using real-world use cases, you will explore the options for network configuration, and understand how to set up, operate, and troubleshoot various Kubernetes networking plugins. In addition to this, you will get to grips with custom resource development and utilization in automation and maintenance workflows. To scale up your knowledge of Kubernetes, you will encounter some additional concepts based on the Kubernetes 1.10 release, such as Promethus, Role-based access control, API aggregation, and more. By the end of this book, you’ll know everything you need to graduate from intermediate to advanced level of understanding Kubernetes.
Table of Contents (16 chapters)

Persistent volumes walk-through

In this section, we will look at the Kubernetes storage conceptual model and see how to map persistent storage into containers so they can read and write. Let's start by looking at the problem of storage. Containers and pods are ephemeral. Anything a container writes to its own filesystem gets wiped out when the container dies. Containers can also mount directories from their host node and read or write. That will survive container restarts, but the nodes themselves are not immortal.

There are other problems, such as ownership for mounted hosted directories when the container dies. Just imagine a bunch of containers writing important data to various data directories on their host and then go away leaving all that data all over the nodes with no direct way to tell what container wrote what data. You can try to record this information, but where...