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

Control structures

In Jinja2, a control structure refers to statements in a template that control the flow of the engine parsing the template. These structures include, but are not limited to, conditionals, loops, and macros. Within Jinja2 (assuming the defaults are in use), a control structure will appear inside blocks of {% ... %}. These opening and closing blocks alert the Jinja2 parser that a control statement is provided instead of a normal string or variable name.

Conditionals

A conditional within a template creates a decision path. The engine will consider the conditional and choose from two or more potential blocks of code. There is always a minimum of two: a path if the conditional is met (evaluated as true), and...