Introduction 

Managing infrastructure on a large-scale is a highly challenging task in modern complex IT environments. Ensuring consistency, compliance, and operational efficiency across numerous systems requires a robust automation strategy. Thats where Ansible steps in. It’s agentless design and human- friendly YAML format enhances configuration management, application deployment, and the task orchestration, which makes it the key to the modern DevOps practices.

If you are new to automation or want to take your skills to the next level, an Ansible and Terraform course can really help. It’s a great way to learn how tools like Ansible and Terraform work together to manage infrastructure as code, and to get hands-on with real-world examples.

In this blog, we will discuss Ansible architecture and its components. We will see how these components work together and also discuss a real-life example for better understanding. By the end, you will know enough to start using it yourself.

Before we jump into the architecture of Ansible, let’s get clear on what Ansible is.

What is Ansible?

Ansible is an IT automation engine for:

• Configuration Management: Making sure systems are set up the same way every time.

• Application Deployment: Installing and updating software without manual steps.

• Task Automation: Handling repetitive jobs across many machines at once.

What makes Ansible special is its simplicity. It’s agentless, meaning you don’t need to install extra software on the machines it controls. It uses SSH (a secure connection method) to get things done.

Let us now move on to our main section, where we will discuss the architecture of Ansible along with its components.

What is Ansible architecture?

Ansible architecture is agentless in nature that uses a control node to manage remote hosts over SSH or WinRM. It executes tasks defined in YAML playbooks via modules. An inventory file lists managed nodes, allowing for simple, push-based configuration management and orchestration without requiring any client-side daemons or special software.

Below, we have discussed components of Ansible architecture in tabular form.

Components of Ansible Architecture	Description
Control Node	Your main computer where you run Ansible
Managed Nodes	The servers or computers you want to control
Inventory	A list of all your managed computers
Modules	Small programs that do specific jobs
Playbooks	Your instruction files that say what to do
Roles	Ways to organize and reuse your work
Plugins	Extra features you can add

Each component of Ansible architecture has a job to do. They work together. Let’s look at each component in detail and see what it does.

Below, we have shown the functioning of each component via Ansible architecture diagram.

Control Node: Your Command Center 

The control node is where you sit and work. It’s the computer with Ansible installed. From here, you write commands and send them out to other machines.

You can use any computer as a control node:

• Your laptop

• A desktop computer

• A dedicated server

As long as it can reach your other machines over the network, you are good to go.

Setting up a control node takes just a few minutes. On most Linux systems, it’s one command:

sudo apt install ansible

Or on a Mac:

brew install ansible

That’s it. No complex installation. No licensing of servers. Just install and go.

The control node does all the thinking. It reads your playbooks, figures out what needs to happen, and sends commands to the right machines. But it never does the actual work. That’s what managed nodes are for.

Managed Nodes: The Workers

These are the machines of the Ansible architecture that do the actual work. They could be:

• Physical servers in your office

• Virtual machines in the cloud

• Containers running applications

• Network devices like routers

• Even IoT devices

You don’t install anything special on these machines. Ansible connects using SSH (for Linux) or WinRM (for Windows). These tools already exist on most systems.

This “agentless” approach saves you time. No software to install. No updates to manage. No security holes to worry about.

Compare this to other tools. Many require you to install agents on every machine. That means:

[webservers]

web1.mycompany.com

web2.mycompany.com

[databases]

db1.mycompany.com

db2.mycompany.com

[development]

dev1.mycompany.com

dev2.mycompany.com

• More setup work

• More things that can break

• More security risks

• More updates to manage

Ansible skips all that hard work. If you can SSH into a machine, Ansible can manage it. Simple as that.

Inventory: Your Address Book

The inventory tells Ansible which machines to work with. It’s like a phone book for your servers.

You can write it as a simple text file:

[webservers]

web1.mycompany.com

web2.mycompany.com

[databases]

db1.mycompany.com

db2.mycompany.com

[development]

dev1.mycompany.com

dev2.mycompany.com

Or pull it from cloud services like AWS or Azure. This lets you manage machines that come and go.

Groups help you organize. Put web servers in one group, databases in another. Then you can run commands on just the machines you need.

You can also add details about each machine:

[webservers]

web1.mycompany.com ansible_user=admin ansible_port=2222

web2.mycompany.com ansible_user=root

[databases]

db1.mycompany.com ansible_host=192.168.1.50

These details tell Ansible how to connect. Different username? Different port? No problem. Put it in the inventory.

For bigger setups, you might use dynamic inventory. This pulls your server list from:

• Cloud providers (AWS, Azure, Google Cloud)

• Container systems (Docker, Kubernetes)

• Monitoring tools

• Your own databases

The inventory grows with you. Start simple with a text file. Move to dynamic inventory when you need it.

Modules: Your Toolbox

Modules are the tools that get work done. Each one has a specific job:

• Install software

• Copy files

• Start or stop services

• Create users

• Manage firewall rules

• And hundreds more

When you need to install a program, you use the package module. Need to copy a file? There’s a module for that, too.

Here’s what installing nginx looks like:

– name: Install nginx

  package:

    name: nginx

    state: present

Simple and clear. No complex scripts are needed.

Ansible comes with over 3,000 modules. That’s a lot of tools in your toolbox. Some popular ones:

• file: Create, delete, or change files and folders

• copy: Copy files to managed nodes

• template: Copy files with variables filled in

• service: Start, stop, or restart services

• user: Create or manage user accounts

• cron: Set up scheduled tasks

• git: Clone or update code repositories

Each module is tested and maintained. You don’t write scripts from scratch. You use proven tools that work.

Here’s a real example using multiple modules:

– name: Set up a developer account

  user:

    name: developer

    groups: sudo

    shell: /bin/bash

– name: Add SSH key for developer

  authorized_key:

    user: developer

    key: “ssh-rsa AAAAB3Nza…”

– name: Create project directory

  file:

    path: /home/developer/project

    state: directory

    owner: developer

Three modules, three tasks, one happy developer with a ready-to-use account.

Playbooks: Automation Instructions

Playbooks tell Ansible what to do, step by step. They’re written in YAML, which looks like a shopping list. 

Here’s a playbook that sets up a web server:

– name: Setup web server

  hosts: webservers

  become: yes

  tasks:

    – name: Install nginx

      package:

        name: nginx

        state: present

    – name: Start and enable nginx

      service:

        name: nginx

        state: started

        enabled: yes

    – name: Open firewall for HTTP

      firewalld:

        service: http

        permanent: yes

        state: enabled

Your automation looks like plain English.

You can also add Variables to make them flexible:

– name: Install web server

  hosts: webservers

  vars:

    web_package: nginx

    web_port: 80

  tasks:

    – name: Install {{ web_package }}

      package:

        name: “{{ web_package }}”

        state: present

Conditionals to handle different situations:

– name: Install web server

  package:

    name: apache2

    state: present

  when: ansible_os_family == “Debian”

– name: Install web server

  package:

    name: httpd

    state: present

  when: ansible_os_family == “RedHat”

Loops to repeat tasks:

– name: Create multiple users

  user:

    name: “{{ item }}”

    state: present

  loop:

    – alice

    – bob

    – charlie

But start simple. Get comfortable with basic playbooks first. Add the fancy stuff when you need it.

Roles: Keeping Things Organized

As you write more playbooks, things can get messy. Roles help you stay organized.

Roles are like a folder system. You put related tasks together. Maybe you have a “webserver” role that:

• Installs nginx

• Copies your website files

• Sets up security

• Configures backups

The folder structure looks like this:

roles/

  webserver/

    tasks/

      main.yml

    handlers/

      main.yml

    templates/

      nginx.conf.j2

    files/

      index.html

    vars/

      main.yml

Each folder has a purpose:

• tasks: The main work happens here

• handlers: Special tasks that run when notified

• templates: Config files with variables

• files: Static files to copy

• vars: Variables for this role

Then you can use that role anywhere:

– name: Setup production servers

  hosts: production

  roles:

    – webserver

    – security

    – monitoring

You write it once, use it many times. Smart and efficient.

Even better, you can share roles. Ansible Galaxy is like an app store for roles. Thousands of pre-made roles are ready to use. Need to install PostgreSQL? There’s a role for that. Want to set up Docker? Use a role.

Plugins: Extra Features

Plugins add extra features to Ansible. They’re like apps on your phone – you add what you need.

Some examples:

• Connection plugins: Change how Ansible connects to machines

• Filter plugins: Transform data in your playbooks

• Callback plugins: Send alerts when tasks finish

• Lookup plugins: Pull data from external sources

Most people start with the built-in features. Add plugins when you need something special.

A useful example is the callback plugin for Slack notifications:

# In ansible.cfg

[defaults]

callback_whitelist = slack

[callback_slack]

webhook_url = https://hooks.slack.com/services/YOUR/WEBHOOK/URL

channel = #ansible-alerts

Now your team gets alerts when playbooks run. Handy for keeping everyone in the loop.

Now you have a good understanding of the different components of Ansible Architecture. Let us now move on to the next section where we will discuss the Ansible workflow.

Ansible Workflow: From Control Node to Target Machine

Let’s walk through what happens when you run Ansible:

1. You write a playbook on your control node

2. You tell Ansible which machines to target (using the inventory)

3. Ansible connects to those machines via SSH

4. It copies the needed modules to each machine

5. The modules run and do their jobs

6. Ansible cleans up and reports back to you

The whole process takes seconds or minutes, not hours. And you can run it again and again with the same results.

This is called “idempotency,” which means “same result every time.” Run a playbook once or a hundred times. The end result is the same. This makes Ansible safe and predictable.

How Ansible keeps your Automation Secure?

Security matters, and Ansible has you covered:

• SSH Keys: No passwords flying around the network

• Sudo Support: Run commands as admin when needed

• Ansible Vault: Lock up sensitive data like passwords

You don’t have to be a security expert. Ansible handles the hard parts for you.

Ansible Vault deserves special mention. It encrypts sensitive data in your playbooks:

ansible-vault create secrets.yml

Type your password, then add your secrets:

database_password: super_secret_pass

api_key: abcd1234efgh5678

Now those secrets are encrypted. Use them in playbooks like normal variables. Ansible decrypts them when needed.

Best Practices for Ansible Architecture

Want to use Ansible like a pro? Follow these tips:

1. Start Small: Don’t automate everything at once. Pick one task and nail it.

2. Use Version Control: Keep your playbooks in Git. Track changes and work with others.

3. Test First: Use the –check flag to see what would happen without making changes.

4. Name Everything: Give clear names to your tasks. “Install nginx” beats “Task 1”.

5. Keep Secrets Safe: Use Ansible Vault for passwords and keys.

6. Organize Early: Start using roles before your playbooks get huge.

7. Document Your Work: Add comments to explain tricky parts. Your future self will thank you.

8. Use Tags: Tag your tasks so you can run just parts of a playbook:

– name: Install nginx

  package:

  name: nginx

  tags:

    – packages

    – web

9. Check Before You Change: Always know what a playbook will do before you run it.

10. Learn From Others: Read playbooks from experienced users. See how they solve problems.

A Real Example: Building a Web Server

Let’s put it all together. We’ll set up a web server from scratch.

First, create your inventory file:

[webservers]

server1.example.com

server2.example.com

Next, write a playbook called setup-web.yml:

– name: Setup web servers

  hosts: webservers

  become: yes

  vars:

    doc_root: /var/www/html

  tasks:

    – name: Update package list

      apt:

        update_cache: yes

      when: ansible_os_family == “Debian”

    – name: Install nginx

      package:

        name: nginx

        state: present

    – name: Create document root

      file:

        path: “{{ doc_root }}”

        state: directory

        mode: ‘0755’

    – name: Create web page

      copy:

        content: |

          <html>

          <head><title>Welcome</title></head>

          <body>

            <h1>Welcome to our site!</h1>

            <p>Powered by Ansible</p>

          </body>

          </html>

        dest: “{{ doc_root }}/index.html”

    – name: Configure nginx

      template:

        src: nginx.conf.j2

        dest: /etc/nginx/sites-available/default

      notify: restart nginx

    – name: Start nginx service

      service:

        name: nginx

        state: started

        enabled: yes

  handlers:

    – name: restart nginx

      service:

        name: nginx

        state: restarted

Run it with:

ansible-playbook -i inventory setup-web.yml

In minutes, you have working web servers. Add more servers to the inventory, and Ansible handles them too. No extra work is needed.

Common Patterns and Solutions

Over time, you’ll see patterns in your work. Here are some common ones:

Rolling Updates

Update servers one at a time to avoid downtime:

– name: Update web servers

  hosts: webservers

  serial: 1

  tasks:

    – name: Update application

      # Your update tasks here

Fact Gathering

Learn about your servers before acting:

– name: Show server info

  debug:

    msg: “{{ ansible_hostname }} runs {{ ansible_distribution }}”

Error Handling

Keep going even if something fails:

– name: Try to install package

  package:

    name: some-package

  ignore_errors: yes

Notifications

Tell other services when things change:

– name: Deploy new code

  git:

    repo: https://github.com/myapp/code

    dest: /opt/myapp

  notify: restart app

Why Choose Ansible?

After using Ansible, going back to manual work feels painful. Here’s why people love it:

• Easy to Learn: If you can read this article, you can write Ansible playbooks.

• No Agents: Nothing to install on managed machines.

• Huge Community: Thousands of pre-built roles and modules.

• Works Everywhere: Linux, Windows, cloud, containers – Ansible handles them all.

• Grows With You: Works for 5 servers or 5,000.

• Plain Text: Everything is text files – easy to read, edit, and share.

• Predictable: Same results every time you run a playbook.

Frequently asked Questions

Q1. What is the architecture of Ansible?

Ansible architecture is an agentless automation tool that is mainly used to manage servers by defining a desired state in YAML playbooks.

Q2. What are the main components of Ansible Architecture?

Main Components of Ansible architecture is:

• Control Node

• Managed Nodes

• Inventory

• Modules

• Playbooks

• Roles

• Plugins

Q3. Do I need to know programming to use Ansible?

No. Ansible playbooks are easy to write – It’s the same as you are writing to-do lists.

Q4. How many servers can Ansible manage?

From one to thousands. It scales with your needs.

Q5. Does Ansible work with Windows?

Yes. It uses WinRM instead of SSH for Windows machines.

Q6. What’s the hardest part about learning Ansible?

Getting started. Once you run your first playbook, everything clicks.

Q7. Can I use Ansible for free?

Yes. The core tool is open source and free forever.

Q8. Can Ansible manage cloud resources?

Absolutely. It integrates with AWS, Azure, Google Cloud, and others. You can create servers, manage storage, and set up networks.

Conclusion

Ansible turns complex IT tasks into simple instructions. Ansible architecture – with control nodes, managed nodes, inventories, modules, playbooks, roles, and plugins – gives you the power to manage servers without any complexity. Start with one simple task. Maybe automate how you install software. Or how you create user accounts. Once you see it work, you will find more ways to use it. The best part? You don’t need to be a programming expert. Write what you want in plain language, and Ansible makes it happen.