Book Image

Learning DevOps

By : Mikael Krief
Book Image

Learning DevOps

By: Mikael Krief

Overview of this book

The implementation of DevOps processes requires the efficient use of various tools, and the choice of these tools is crucial for the sustainability of projects and collaboration between development (Dev) and operations (Ops). This book presents the different patterns and tools that you can use to provision and configure an infrastructure in the cloud. You'll begin by understanding DevOps culture, the application of DevOps in cloud infrastructure, provisioning with Terraform, configuration with Ansible, and image building with Packer. You'll then be taken through source code versioning with Git and the construction of a DevOps CI/CD pipeline using Jenkins, GitLab CI, and Azure Pipelines. This DevOps handbook will also guide you in containerizing and deploying your applications with Docker and Kubernetes. You'll learn how to reduce deployment downtime with blue-green deployment and the feature flags technique, and study DevOps practices for open source projects. Finally, you'll grasp some best practices for reducing the overall application lead time to ensure faster time to market. By the end of this book, you'll have built a solid foundation in DevOps, and developed the skills necessary to enhance a traditional software delivery process using modern software delivery tools and techniques
Table of Contents (23 chapters)
Free Chapter
1
Section 1: DevOps and Infrastructure as Code
6
Section 2: DevOps CI/CD Pipeline
9
Section 3: Containerized Applications with Docker and Kubernetes
12
Section 4: Testing Your Application
16
Section 5: Taking DevOps Further

Using Ansible in a Packer template

We have just seen how to write a Packer template that uses command scripts (for example, apt-get), but it is also possible to use Ansible playbooks to create an image. Indeed, when we use IaC to configure VMs, we are often used to configuring the VMs directly using Ansible before thinking about making them into VM images.

What is interesting about Packer is that we can reuse the same playbook scripts that we used to configure VMs to create our VM images. So, it's a huge time saver because we don't have to rewrite the scripts.

To put this into practice, we will write the following:

  • An Ansible playbook that installs nginx
  • A Packer template that uses Ansible with our playbook

Let's start with the writing of the Ansible playbook.

Writing...