Introduction to Ansible Link to heading

Ansible is an open-source automation platform that simplifies configuration management, application deployment, and task automation. It uses a simple YAML-based language (YAML Ain’t Markup Language) to describe automation jobs in a way that approaches plain English.

Why Use Ansible? Link to heading

  • Agentless: No need to install any additional software on the nodes you want to automate
  • Idempotent: Can be run multiple times without side effects
  • Simple: Uses YAML syntax (called Playbooks) which are easy to write and understand
  • Powerful: Can manage complex deployments and orchestrate entire application lifecycles
  • Extensible: Large collection of built-in modules and the ability to create custom ones

Basic Ansible Concepts Link to heading

Inventory Link to heading

Ansible works against multiple systems in your infrastructure at the same time. It does this by selecting portions of systems listed in your inventory file (by default located at /etc/ansible/hosts).

Example inventory file:

[webservers]
web1.example.com
web2.example.com

[database]
db1.example.com

Playbooks Link to heading

Playbooks are Ansible’s configuration, deployment, and orchestration language. They can describe a policy you want your remote systems to enforce, or a set of steps in a general IT process.

Example playbook (webserver.yml):

---
- name: Install and start Apache
  hosts: webservers
  become: yes
  
  tasks:
    - name: Install Apache
      apt:
        name: apache2
        state: present
        update_cache: yes
    
    - name: Start Apache service
      service:
        name: apache2
        state: started
        enabled: yes

Modules Link to heading

Modules are the units of code Ansible executes. Each module is mostly standalone and can be written in any language that can return JSON.

Common modules include:

  • apt/yum: Package management
  • copy: Copy files to remote locations
  • file: Set attributes of files, symlinks, and directories
  • service: Manage services
  • template: Template a file out to a remote server

Getting Started Link to heading

  1. Installation (on Ubuntu/Debian):

    sudo apt update
sudo apt install -y ansible

  2. Verify Installation:

    ansible --version

  3. Test Connection:

    ansible all -i inventory.ini -m ping

Best Practices Link to heading

  1. Use Roles: Organize your playbooks into reusable components
  2. Use Variables: Make your playbooks more flexible with variables
  3. Use Vault: Store sensitive data using Ansible Vault
  4. Tag Your Tasks: Makes it easier to run specific parts of a playbook
  5. Documentation: Always document your playbooks and roles

Conclusion Link to heading

Ansible provides a simple yet powerful way to automate IT infrastructure. Its agentless architecture and easy-to-understand YAML syntax make it accessible for beginners while being powerful enough for complex automation tasks.

Further Reading Link to heading