Book Image

The Kubernetes Book

By : Nigel Poulton, Pushkar Joglekar
Book Image

The Kubernetes Book

By: Nigel Poulton, Pushkar Joglekar

Overview of this book

Kubernetes is the leading orchestrator of cloud-native apps. With knowledge of how to work with Kubernetes, you can easily deploy and manage applications on the cloud or in your on-premises data center. The book begins by introducing you to Kubernetes and showing you how to install it. You’ll learn how to use Kubernetes Services and bring stable and reliable networking to apps that are deployed on Kubernetes. You'll delve deep into the powerful storage subsystem of Kubernetes and learn how to leverage the variety of external storage backends in your applications. As the book progresses, it shows you how to use features such as DaemonSets, Helm, and RBAC to enhance your Kubernetes applications. You'll explore the six categories of identifying vulnerabilities and look at a few ways to prevent and mitigate them. You'll also look at ways to secure the software delivery pipeline by discussing some image-related best practices. The book ends by sharing with you some resources that’ll help take your Kubernetes knowledge to the next level. By the end of the book, you’ll have the confidence and skills to leverage all the features of Kubernetes to develop scalable applications.
Table of Contents (23 chapters)
Free Chapter
1
Chapter 1
3
Chapter 2
5
Chapter 3
7
Chapter 4
9
Chapter 5
11
Chapter 6
13
Chapter 7
15
Chapter 8
17
Chapter 9
19
Chapter 10
21
Chapter 11

Masters and Nodes

A Kubernetes cluster is made of masters and nodes. These are Linux hosts that can be VMs, bare metal servers in your data center, or instances in a private or public cloud.

Masters (Control Plane)

A Kubernetes master is a collection of system services that make up the control plane of the cluster.

The simplest setups run all the master services on a single host. However, this is only suitable for labs and test environments. For production environments, multi-master high availability (HA) is a must-have. This is why the major cloud providers implement HA masters as part of their Kubernetes-as-a-Service platforms, such as Azure Kubernetes Service (AKS), AWS Elastic Kubernetes Service (EKS), and Google Kubernetes Engine (GKE).

Generally speaking, running three or five replicated masters in an HA configuration is recommended.

It's also considered good practice not to run user applications on masters. This allows masters to concentrate entirely on managing...