Mastering Ansible

Course Description Mastering Ansible is a step-by-step journey of learning Ansible for configuration management and orchestration. The course is designed as a journey through configuring a realistic application stack from the ground up. Instead of going page-by-page through the Ansible documentation, topics are ordered to align with the growing complexity of our application as we build it up and refactor it. In addition to the core concepts of configuration with Ansible, we spend time on building tools to help us maintain and troubleshoot our application. The goal is to have a workflow where all of the configuration and troubleshooting is done through ansible playbooks that can be committed to a repository and improved over time. The course is divided into 6 sections, starting with initial installation and foundational concepts. Starting in section 3, we build up a sample application environment layer-by-layer, learning a new concept in each lecture. After the application is up and running, we refactor our setup in section 4 with an emphasis on modularity and encapsulation. In section 5, we optimize our code and learn about techniques to reduce the playbook execution time. The course finishes with a final section on troubleshooting and testing. For each lecture, we introduce a new Ansible concept and apply it to our playbooks. For most lectures, we execute the new concept in the demo environment so you can see what the output should look like. In the notes of each lecture, you'll find a link to the relevant documentation pages, along with a snapshot of the codebase at the end of that lecture. This course was built with Ansible version 1.9.3, applied to a 3-tiered web application environment leveraging NGINX, Apache2, Python, and MySQL on Ubuntu Linux servers. We do not cover administering Windows servers in this course. This course is designed as an introduction to Ansible, but also as a guide for engineers interested in configuration management, orchestration, infrastructure-as-code, and devops principles.

Requirements
You should have a Linux or Mac OS X computer, or access to at lease one Linux virtual machine for installing Ansible.
You'll need a code editor or IDE of your choice.
You'll need a terminal and ssh client for running Ansible against target hosts.
You should have access to 5 Linux servers (bare-metal or virtual machine) if you want to setup the course environment and follow along step-by-step.

Who is the target audience? The course is designed for students who have little or no experience with Ansible, but are familiar with Linux systems administration concepts. No programming or previous automation experience is required. If you've never logged into a Linux shell and run commands before, you will learn the Ansible syntax but you may not understand the 'why' behind the tasks that we configure. We try to explain all systems concept that we cover, but we aren't starting from the beginning with Linux in this course.

Introduction  Introduction Configuration Management & Orchestration

Preparation  Environment setup Installation

Foundation  Inventory Pt 1 Inventory Pt 2 Host Selection Tasks Plays Playbook Execution Foundation Concepts

Playbooks  Playbooks Introduction Packages: apt Packages: become Packages: with_items Services: service Support Playbook 1 - Stack Restart Services: apache2_module, handlers, notify Files: copy Application Modules: pip Files: file Files: template Files: lineinfile Application Modules: mysql_db, mysql_user Support Playbook 2 - Stack Status: wait_for Support Playbook 2 - Stack Status: uri, register, fail, when Playbooks Summary Playbook Concepts

Modular Configuration with Roles  Roles Overview Converting to Roles: tasks, handlers Converting to Roles: files, templates Site.yml: include Variables: facts Variables: defaults Variables: vars Variables: with_dict Selective Removal: shell, register, with_items, when Variables - continued Variables: vars_files, group_vars Variables: vault External Roles & Galaxy Variables

Advanced Execution  Advanced Execution Introduction Removing Unnecessary Steps: gather_facts Extracting Repetitive Tasks: cache_valid_time Limiting Execution by Hosts: limit Limiting Execution by Tasks: tags Idempotence: changed_when, failed_when Accelerated Mode and Pipelining

Troubleshooting, Testing & Validation  Troubleshooting Ordering Problems Jumping to Specific Tasks: list-tasks, step, start-at-task Retrying Failed Hosts Syntax-Check & Dry-Run: syntax-check, check Debugging: debug Testing Concepts

Appendix  Authentication with SSH Keys A Brief Overview of YAML A Brief Overview of Jinja2 Dev Environment with Docker