Book Image

Docker for Developers

By : Richard Bullington-McGuire, Andrew K. Dennis, Michael Schwartz
2 (1)
Book Image

Docker for Developers

2 (1)
By: Richard Bullington-McGuire, Andrew K. Dennis, Michael Schwartz

Overview of this book

Docker is the de facto standard for containerizing apps, and with an increasing number of software projects migrating to containers, it is crucial for engineers and DevOps teams to understand how to build, deploy, and secure Docker environments effectively. Docker for Developers will help you understand Docker containers from scratch while taking you through best practices and showing you how to address security concerns. Starting with an introduction to Docker, you’ll learn how to use containers and VirtualBox for development. You’ll explore how containers work and develop projects within them after you’ve explored different ways to deploy and run containers. The book will also show you how to use Docker containers in production in both single-host set-ups and in clusters and deploy them using Jenkins, Kubernetes, and Spinnaker. As you advance, you’ll get to grips with monitoring, securing, and scaling Docker using tools such as Prometheus and Grafana. Later, you’ll be able to deploy Docker containers to a variety of environments, including the cloud-native Amazon Elastic Kubernetes Service (Amazon EKS), before finally delving into Docker security concepts and best practices. By the end of the Docker book, you’ll be able to not only work in a container-driven environment confidently but also use Docker for both new and existing projects.
Table of Contents (21 chapters)
1
Section 1: An Introduction to Docker – Containers and Local Development
6
Section 2: Running Docker in Production
14
Section 3: Docker Security – Securing Your Containers

Scaling your Kubernetes cluster

To support more traffic and more applications, your Kubernetes cluster may need to grow beyond its initial size. You can use both manual methods and dynamic programmed methods to do this, especially if you are working with a cloud-based Kubernetes cluster. To scale out an application, you need to control two dimensions: the number of pods running a particular application and the number of nodes in a cluster. You can't scale the number of pods infinitely on a cluster with the same number of nodes; practical limits related to CPU, memory, and network concerns will ultimately demand that the cluster scales out the number of nodes as well.

The method that's used to scale out a cluster will vary considerably, depending on the cloud vendor and Kubernetes distribution. The Kubernetes documentation explains both the general process and some specific instructions for clusters running in the Google and Microsoft Azure clouds:

https://kubernetes...