Ansible Deep Dive
Welcome
A first-principles guide to Ansible — what each piece does, how the model fits together, when to reach for it, and where the failure modes hide. Ansible is agentless, push-based, and idempotent, with no state file: the managed node itself is the source of truth, re-converged on every run. The examples run on plain Linux servers and stay cloud-neutral.
About This Course
Ansible has a reputation for being quick to start and deceptively deep to run well. You can write a playbook that installs nginx on three servers in an afternoon. Running automation across a real fleet — many hosts, ordered rolling deploys, secrets, environments that must not drift — is where the actual craft lives, and where most introductions stop.
This course covers both ends. It explains Ansible from first principles, in the order that makes the model click: what configuration management solves and why Ansible's agentless, push-based, no-state design is different, then inventory, modules, playbooks, variables and facts, templating, control flow, roles, and secrets — before the parts of running Ansible at scale that bite you: orchestration, performance, testing, and automation from a controller.
Every topic follows a consistent shape: what it is, how it works, when to use it, when not to, the mistakes that cost real outages, and the practices that prevent them. Where two approaches compete — command versus a real module, import versus include, a static inventory versus a dynamic one — the course compares them and says when each fits, instead of leaving that judgment to you.
Who This Is For
Engineers who configure or operate servers, and those moving into that work. A beginner can read it in order and build a mental model from zero — no prior Ansible is assumed, only basic comfort on the Linux command line. An experienced engineer can jump to a chapter to settle a decision or close a gap, including someone who knows a provisioning tool like Terraform and wants the configuration-management half of the picture.
A Note on Ansible, ansible-core, and Automation Platform
The course teaches community ansible-core plus collections — the way most people actually run Ansible, from a laptop or a CI runner over SSH. Red Hat's commercial layer (AWX, Ansible Automation Platform, execution environments, and ansible-navigator) is real and worth knowing, so it gets a dedicated chapter at the end rather than being assumed throughout. Everything you learn about inventory, playbooks, roles, and variables applies identically whether you run it from a terminal or from a controller.
Ansible manages anything it can reach over a connection — Linux and Windows hosts, network gear, cloud APIs, containers. But every example has to target something concrete, so this course manages Linux servers over SSH throughout and stays cloud-neutral, with one chapter on dynamic inventory for the major clouds. The concepts transfer to any target; Linux is the vehicle that keeps the examples real instead of abstract.
What You Should Already Know
- Command-line comfort on Linux — running commands, editing files, environment variables
- A basic feel for how servers work — SSH, packages, services, and config files under
/etc - Version control with Git at a basic level — commits, branches, and pull requests
- What YAML is, at the level of reading an indented key-and-value document
- No prior Ansible or configuration-management experience required
How the Course Is Built
The thirteen chapters are ordered so the early ones teach the core and the later ones build on it. Foundations and inventory come first, because Ansible does nothing until it knows which hosts it manages. Then modules and playbooks, variables and facts, templating and control flow, roles and secrets — the language of Ansible — before the chapters on orchestration at scale, performance and plugins, testing, and running Ansible from a controller in production.
A running example threads through the whole book: a small SaaS shop called Larkspur. It starts as one hand-built web stack — nginx and an app on a couple of web servers, PostgreSQL on a database server — brought under Ansible management piece by piece. By the later chapters it has grown into a multi-environment fleet behind a load balancer, deployed with zero downtime and run from a controller in CI. A few principles run through every chapter and explain why the course is shaped the way it is.
Chapter Map
command and shell break idempotency, reading the docs, and check and diff mode.
become, and the lifecycle of a run.
set_fact and registered results, magic variables, fact caching, and variable hygiene.
template module, the workhorse filters, tests and conditionals, lookups that run on the control node, and whitespace control.
when truthiness traps, loops, blocks with rescue and always, failure control, tags for selective runs, and the static-versus-dynamic import/include distinction.
forks versus serial, delegation to a load balancer, async tasks, batching and throttling, and a full zero-downtime rolling deploy.
ansible.cfg precedence, connection plugins, the broader plugin ecosystem, performance tuning from pipelining to fact caching, accelerators and their cost, and debugging.
yamllint and ansible-lint, Molecule for role testing, the second-run idempotency rule, CI/CD pipelines, and testing collections.
ansible-navigator, AWX and Automation Platform, GitOps, and where Ansible sits next to Terraform.
Disclaimer
This course is an independent educational project created and maintained by Sergey Okinchuk. It is provided for learning and reference purposes only.
No affiliation. This course is not affiliated with, sponsored by, endorsed by, or officially connected to Red Hat, Inc., the Ansible project, the OpenSSF, or any other company or project mentioned. All opinions, interpretations, and recommendations expressed are those of the author.
Trademarks. "Ansible" and "Ansible Automation Platform" are trademarks of Red Hat, Inc. "Puppet", "Chef", "SaltStack", "Terraform", and all other product names, logos, and brands are the property of their respective owners. Use of these names and marks is for identification and educational purposes only and does not imply any endorsement.
Accuracy and currency. Ansible evolves quickly — ansible-core ships on a fast cadence, and modules, collections, defaults, and command-line flags drift between versions. Facts in this course reflect the author's understanding at the time of writing and may not be current. Always consult the official Ansible documentation as the authoritative source before making operational decisions.
No warranty. This material is provided "as is" without warranty of any kind. Playbooks and commands are illustrative, not production-ready, and may cause disruption if run against real systems. The author accepts no liability for any loss or damage arising from reliance on the content.