Book Image

Mastering Ansible, 4th Edition - Fourth Edition

By : James Freeman, Jesse Keating
Book Image

Mastering Ansible, 4th Edition - Fourth Edition

By: James Freeman, Jesse Keating

Overview of this book

Ansible is a modern, YAML-based automation tool (built on top of Python, one of the world’s most popular programming languages) with a massive and ever-growing user base. Its popularity and Python underpinnings make it essential learning for all in the DevOps space. This fourth edition of Mastering Ansible provides complete coverage of Ansible automation, from the design and architecture of the tool and basic automation with playbooks to writing and debugging your own Python-based extensions. You'll learn how to build automation workflows with Ansible’s extensive built-in library of collections, modules, and plugins. You'll then look at extending the modules and plugins with Python-based code and even build your own collections — ultimately learning how to give back to the Ansible community. By the end of this Ansible book, you'll be confident in all aspects of Ansible automation, from the fundamentals of playbook design to getting under the hood and extending and adapting Ansible to solve new automation challenges.
Table of Contents (18 chapters)
Section 1: Ansible Overview and Fundamentals
Section 2: Writing and Troubleshooting Ansible Playbooks
Section 3: Orchestration with Ansible

Chapter 11: Minimizing Downtime with Rolling Deployments

Ansible is well suited to the task of upgrading or deploying applications in a live service environment. Of course, application deployments and upgrades can be approached with a variety of different strategies. The best approach depends on the application itself, the capabilities of the infrastructure the application runs on, and any promised service-level agreements (SLAs) with the users of the application. Whatever the approach, it is vital that the application deployment or upgrade is controlled, predictable, and repeatable in order to ensure that users experience a stable service while automated deployments occur in the background. The last thing anyone wants is an outage caused by unexpected behavior from their automation tool; an automation tool should be trustworthy and not an additional risk factor.

Although there is a myriad of choices, some deployment strategies are more common than others, and in this chapter, we...