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

Executing Ansible

We have so far seen the installation of Ansible, listed the hosts in the inventory, and set up our Ansible playbook; now, we can run Ansible to configure our VMs.

For this, we will run the Ansible tool with the ansible-playbook command, like this:

ansible-playbook -i inventory playbook.yml

The basic options of this command are as follows:

  • The -i argument with the inventory file path
  • The path of the playbook file

The following is the execution of this command:

The execution of this command applies the playbook to the hosts in the inventory in several steps:

  1. Gathering facts: Ansible checks that the hosts are reachable.
  2. The tasks' playbook is executed on hosts.
  3. PLAY Recap: This is the status of the changes that were executed on each host; the value of this status can be as follows:

ok

This is the number of playbook tasks that have been correctly...