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

Creating a site-wide playbook, nesting, and using include statements


As a best practice, we will create a top-level file, which will contain the blueprint of our complete infrastructure. Technically, we can include everything that we need to configure inside just one file. However, that would have two problems:

  • It would quickly get out of control as we start adding tasks, variables, and handlers to this single file. It would be a nightmare to maintain such code.

  • It would also be difficult to reuse and share such code. One of the advantages of using a tool such as Ansible is its ability to separate data from code. Data is organization-specific, and code is generic. This generic code can then be shared with others. However, if you write everything in a single file, it would be impossible to do so.

To avoid this problem, we will start organizing our code in a modular fashion, as follows:

  • We will create roles for each of the applications that we need to configure. In this case, it is Nginx

  • Our web...