Book Image

Ansible Playbook Essentials

By : Gourav Shah, GOURAV JAWAHAR SHAH
Book Image

Ansible Playbook Essentials

By: Gourav Shah, GOURAV JAWAHAR SHAH

Overview of this book

Ansible Playbook Essentials will show you how to write a blueprint of your infrastructure, encompassing multitier applications using Ansible's playbooks. Beginning with basic concepts such as plays, tasks, handlers, inventory, and YAML Ain't Markup Language (YAML) syntax that Ansible uses, you'll understand how to organize your code into a modular structure. Building on this, you will study techniques to create data-driven playbooks with variables, templates, logical constructs, and encrypted data, which will further strengthen your application skills in Ansible. Adding to this, the book will also take you through advanced clustering concepts, such as discovering topology information about other nodes in the cluster and managing multiple environments with isolated configurations. As you approach the concluding chapters, you can expect to learn about orchestrating infrastructure and deploying applications in a coordinated manner. By the end of this book, you will be able to design solutions to your automation and orchestration problems using playbooks quickly and efficiently.
Table of Contents (20 chapters)
Ansible Playbook Essentials
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Setting Up the Learning Environment
References
Index

Chapter 6. Iterative Control Structures – Loops

You learned about conditional controls in the previous chapter. Our journey into Ansible's world of control structures continues with iterative controls. Often, we need to create a list of directories, install a bunch of packages, or define and walk over nested hashes or dictionaries. Traditional programming languages use the for or while loops for iteration. Ansible replaces them with the with statements.

In this chapter, we are going to learn about:

  • How to use iterative controls using the with statements

  • How to loop arrays to create multiple objects at once

  • How to define nested hashes and walk over them to create data-driven roles