Why Ansible

Configuration Management

Configuration management is the practice of defining and maintaining system configurations consistently across environments. Instead of manually installing packages, editing files, and restarting services on each server, you describe the desired state declaratively and let a tool enforce it.

Ansible is an open-source automation engine that handles configuration management, application deployment, and orchestration. It uses YAML syntax to express desired state, making playbooks readable by anyone on the team — not just operations engineers.

Agentless Architecture

Unlike Puppet, Chef, or Salt, Ansible requires no agent on managed nodes. It connects over SSH (or WinRM for Windows), executes commands, and disconnects. This eliminates agent management overhead, version conflicts, and the need for a dedicated pull cycle.

# Ansible pushes tasks to managed nodes via SSH
# No daemon, no agent, no pull interval

# What happens on each run:
# 1. Control node connects via SSH
# 2. Generates and transfers a Python module
# 3. Executes the module on the remote host
# 4. Returns JSON output to the control node
# 5. Cleans up temporary files

Push vs Pull Models

Push-based tools give you immediate visibility — when you run a playbook, you see results in real time. Pull-based tools offer eventual consistency but can make it harder to know exactly when changes were applied.

Ansible vs Terraform

Ansible and Terraform are often mentioned together but solve different problems. Terraform provisions infrastructure (VMs, networks, DNS records). Ansible configures what runs on that infrastructure (packages, configs, services).

# Terraform creates the VM
# terraform apply -> provisions EC2 instance

# Ansible configures what runs on it
- name: Configure web server
  hosts: webservers
  tasks:
    - name: Install nginx
      package:
        name: nginx
        state: present

    - name: Start nginx
      service:
        name: nginx
        state: started
        enabled: yes

Primary Use Cases

• Server provisioning — install packages, create users, configure services
• Application deployment — push code, manage dependencies, restart services
• Compliance enforcement — audit system state, apply CIS benchmarks
• Orchestration — coordinate multi-tier deployments across hundreds of servers
• Cloud automation — manage AWS, Azure, GCP resources alongside on-premises