Book Image

Modern DevOps Practices

By : Gaurav Agarwal
Book Image

Modern DevOps Practices

By: Gaurav Agarwal

Overview of this book

Containers have entirely changed how developers and end-users see applications as a whole. With this book, you'll learn all about containers, their architecture and benefits, and how to implement them within your development lifecycle. You'll discover how you can transition from the traditional world of virtual machines and adopt modern ways of using DevOps to ship a package of software continuously. Starting with a quick refresher on the core concepts of containers, you'll move on to study the architectural concepts to implement modern ways of application development. You'll cover topics around Docker, Kubernetes, Ansible, Terraform, Packer, and other similar tools that will help you to build a base. As you advance, the book covers the core elements of cloud integration (AWS ECS, GKE, and other CaaS services), continuous integration, and continuous delivery (GitHub actions, Jenkins, and Spinnaker) to help you understand the essence of container management and delivery. The later sections of the book will take you through container pipeline security and GitOps (Flux CD and Terraform). By the end of this DevOps book, you'll have learned best practices for automating your development lifecycle and making the most of containers, infrastructure automation, and CaaS, and be ready to develop applications using modern tools and techniques.
Table of Contents (19 chapters)
1
Section 1: Container Fundamentals and Best Practices
7
Section 2: Delivering Containers
15
Section 3: Modern DevOps with GitOps

Docker architecture

As we already know, Docker uses the build once, run anywhere concept. Docker packages applications into images. Docker images form the blueprint of containers, so a container is an instance of an image.

A container image packages applications and their dependencies, so they are a single mutable unit you can run in any machine that runs Docker. You can also visualize them as a snapshot of the container.

We can build and store Docker images in a Docker Registry such as Docker Hub, and then download and use those images in the system where we want to deploy them. Images comprise several layers, so it helps to break images into multiple parts. The layers tend to be reusable stages that other images can build upon. This also means that we don't have to transmit the entire image over a network when we change images and just transmit the delta, which saves a lot of network I/O. We will talk about the layered filesystem in detail later in this chapter.

The...