Ansible

Ansible is an agentless automation tool. It handles Configuration Management (installing Nginx, editing configs). 2025 sees the Automation Platform 2.5 unified UI and AI Lightspeed assistance.

When to Use

• Configuration Mgmt: Terraform creates the VM, Ansible installs the software inside it.
• Agentless: No software to install on targets. Needs only SSH.
• Network Automation: Configuring Routers/Switches.

Quick Start

# playbook.yml
- name: Configure Webservers
  hosts: web
  become: true
  tasks:
    - name: Install Nginx
      ansible.builtin.apt:
        name: nginx
        state: present

    - name: Start Service
      ansible.builtin.service:
        name: nginx
        state: started

Core Concepts

Inventory

List of hosts (hosts.ini or YAML). Can be dynamic (AWS plugin).

Playbooks

YAML files defining the desired state.

Roles / Collections

Reusable units of code. Download from Ansible Galaxy.

Best Practices (2025)

Do:

• Use Collections: The modern packaging format. ansible.builtin is better than short modules.
• Use ansible-lint: Enforce best practices.
• Idempotency: Ensure running a playbook twice produces the same result without errors.

Don’t:

• Don’t use shell module: Unless absolutely necessary. Use specific modules (user, file, apt) for key tasks.

References

• Ansible Documentation