Book Image

Mastering Ansible. - Third Edition

By : James Freeman, Jesse Keating
Book Image

Mastering Ansible. - Third Edition

By: James Freeman, Jesse Keating

Overview of this book

Automation is essential for success in the modern world of DevOps. Ansible provides a simple, yet powerful, automation engine for tackling complex automation challenges. This book will take you on a journey that will help you exploit the latest version's advanced features to help you increase efficiency and accomplish complex orchestrations. This book will help you understand how Ansible 2.7 works at a fundamental level and will also teach you to leverage its advanced capabilities. Throughout this book, you will learn how to encrypt Ansible content at rest and decrypt data at runtime. Next, this book will act as an ideal resource to help you master the advanced features and capabilities required to tackle complex automation challenges. Later, it will walk you through workflows, use cases, orchestrations, troubleshooting, and Ansible extensions. Lastly, you will examine and debug Ansible operations, helping you to understand and resolve issues. By the end of the book, you will be able to unlock the true power of the Ansible automation engine and tackle complex, real- world actions with ease.
Table of Contents (17 chapters)
Free Chapter
1
Section 1: Ansible Overview and Fundamentals
6
Section 2: Writing and Troubleshooting Ansible Playbooks
12
Section 3: Orchestration with Ansible

Iterative tasks with loops

Loops deserve a special mention in this chapter. So far, we have focused on controlling the flow of a playbook in a top-to-bottom fashion—we have changed the various conditions that might be evaluated as the playbook runs, and we have also focused on creating concise efficient code. What happens, however, if you have a single task, but need to run it against a list of data; for example, creating several user accounts, or directories, or indeed something more complex.

Looping changed in Ansible 2.5—prior to this, loops were generally created with keywords such as with_items. Although some backward compatibility remains, it is advisable to move to the newer loop keyword instead.

Let's take a simple example—we need to create two directories. Create loop.yaml as follows:

---
- name: looping demo
hosts: localhost
gather_facts: false...