Book Image

Learn Docker - Fundamentals of Docker 19.x - Second Edition

By : Dr. Gabriel N. Schenker
Book Image

Learn Docker - Fundamentals of Docker 19.x - Second Edition

By: Dr. Gabriel N. Schenker

Overview of this book

Containers enable you to package an application with all the components it needs, such as libraries and other dependencies, and ship it as one package. Docker containers have revolutionized the software supply chain in both small and large enterprises. Starting with an introduction to Docker fundamentals and setting up an environment to work with it, you’ll delve into concepts such as Docker containers, Docker images, and Docker Compose. As you progress, the book will help you explore deployment, orchestration, networking, and security. Finally, you’ll get to grips with Docker functionalities on public clouds such as Amazon Web Services (AWS), Azure, and Google Cloud Platform (GCP), and learn about Docker Enterprise Edition features. Additionally, you’ll also discover the benefits of increased security with the use of containers. By the end of this Docker book, you’ll be able to build, ship, and run a containerized, highly distributed application on Docker Swarm or Kubernetes, running on-premises or in the cloud.
Table of Contents (25 chapters)
1
Section 1: Motivation and Getting Started
4
Section 2: Containerization, from Beginner to Black Belt
11
Section 3: Orchestration Fundamentals and Docker Swarm
18
Section 4: Docker, Kubernetes, and the Cloud

Chapter 16

Here are some sample answers to the questions presented in this chapter:

  1. Assuming we have a Docker image in a registry for the two application services, the web API and Mongo DB, we then need to do the following:
    • Define a deployment for Mongo DB using a StatefulSet; let's call this deployment db-deployment. The StatefulSet should have one replica (replicating Mongo DB is a bit more involved and is outside the scope of this book).
    • Define a Kubernetes service called db of the ClusterIP type for db-deployment.
    • Define a deployment for the web API; let's call it web-deployment. Let's scale this service to three instances.
    • Define a Kubernetes service called api of the NodePort type for web-deployment.
    • If we use secrets, then define those secrets directly in the cluster using kubectl...