Ansible vs Terraform
Ansible and Terraform are both widely used tools for IT automation, but they serve different purposes and are used in different scenarios. Below is a simple comparison of their key differences:
1. Approach to Infrastructure Management
| Feature |
Ansible |
Terraform |
| Purpose |
Configuration management, orchestration |
Infrastructure as Code (IaC) |
| How it Works |
Manages existing infrastructure (configures servers, installs software, deploys apps) |
Creates, modifies, and destroys infrastructure resources (VMs, networks, databases) |
| Execution Mode |
Push-based (commands are sent directly to target machines) |
Pull-based (interacts with APIs of cloud providers) |
2. Resource Management
| Feature |
Ansible |
Terraform |
| Primary Use |
Manages software and OS configurations on existing infrastructure |
Builds and manages cloud infrastructure from scratch |
| Scope |
Servers, applications, networking, containers |
VMs, databases, load balancers, networks, storage |
3. Configuration Language
| Feature |
Ansible |
Terraform |
| Language |
YAML (Playbooks) |
HCL (HashiCorp Configuration Language) |
| Approach |
Describes tasks and steps to execute |
Describes the desired end state of infrastructure |
4. Imperative vs. Declarative Approach
| Feature |
Ansible |
Terraform |
| Type |
Partially imperative, partially declarative |
Fully declarative |
| Execution |
Defines specific steps to be executed (imperative) but can also define desired states (declarative) |
Only defines the desired state, Terraform figures out how to achieve it |
5. State Management
| Feature |
Ansible |
Terraform |
| State Tracking |
No (does not store infrastructure state) |
Yes (stores infrastructure state in a .tfstate file) |
| Effect |
Runs the same tasks each time without tracking changes |
Compares actual infrastructure state with the defined configuration and applies only necessary changes |
6. Idempotency (Ensuring Same Result on Re-Runs)
| Feature |
Ansible |
Terraform |
| Idempotency |
Possible, but depends on how Playbooks are written |
Built-in, Terraform ensures no unnecessary changes |
7. Use Cases and Integration
| Feature |
Ansible |
Terraform |
| Use Cases |
Server configuration, app deployment, OS package management, automation tasks |
Infrastructure provisioning, cloud resource management, networking |
| Integration |
Works with SSH, API-based tools, and various OS |
Works with cloud providers (AWS, Azure, GCP), virtualization, and API-driven platforms |
8. Orchestration Capabilities
| Feature |
Ansible |
Terraform |
| Orchestration |
Yes, supports running tasks in sequence, handling dependencies |
No, focuses on infrastructure management, not workflow execution |
| Feature |
Ansible |
Terraform |
| Supported Platforms |
Works on any system with SSH or API access |
Works mainly with cloud providers and virtualization platforms |
| Scenario |
Best Tool |
| Configuring servers, installing software, managing applications |
Ansible |
| Creating infrastructure (VMs, databases, networks) |
Terraform |
| Automating operational tasks on existing servers |
Ansible |
| Managing cloud environments and infrastructure lifecycle |
Terraform |
| Orchestrating multi-step workflows and deployments |
Ansible |
| Enforcing desired infrastructure state over time |
Terraform |
| Using both for complete automation (Terraform for infra, Ansible for config) |
Ansible + Terraform |
Conclusion
- Use Ansible if you need to configure servers, install software, or deploy applications.
- Use Terraform if you need to provision and manage cloud infrastructure.
- Combine both: Terraform for infrastructure creation, Ansible for server configuration.