Book Image

Mastering Ansible, Second Edition - Second Edition

By : Jesse Keating
Book Image

Mastering Ansible, Second Edition - Second Edition

By: Jesse Keating

Overview of this book

This book provides you with the knowledge you need to understand how Ansible 2.1 works at a fundamental level and leverage its advanced capabilities. You'll learn how to encrypt Ansible content at rest and decrypt data at runtime. You will master the advanced features and capabilities required to tackle the complex automation challenges of today and beyond. You will gain detailed knowledge of Ansible workflows, explore use cases for advanced features, craft well thought out orchestrations, troubleshoot unexpected behaviour, and extend Ansible through customizations. Finally, you will discover the methods used to examine and debug Ansible operations, helping you to understand and resolve issues. By the end of the book, the readers will be able to unlock the true power of the Ansible automation engine and will tackle complex real world actions with ease.
Table of Contents (16 chapters)
Mastering Ansible - Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Expanding and contracting


An alternative to the in-place upgrade strategy is the expand and contract strategy. This strategy has become popular of late thanks to the self-service nature of on-demand infrastructure, such as cloud computing or virtualization pools. The ability to create new servers on demand from a large pool of available resources means that every deployment of an application can happen on brand new systems. This strategy avoids a host of issues, such as a build up of cruft on long running systems, such as:

  • The configuration files no longer managed by Ansible are left behind

  • The run-away processes consume resources in the background

  • Things manually changed by humans with shell access to the server

Starting afresh each time also removes differences between an initial deployment and an upgrade. The same code path can be used, reducing the risk of surprises while upgrading an application. This type of an install can also make it extremely easy to roll back if the new version does...