Ansible

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