In the world of Infrastructure as Code (IaC), Terraform and Ansible is one of the leading tools, each with unique strengths. Knowing how they differ and how they can work together is essential for modern infrastructure management.
Terraform
Developed by HashiCorp, Terraform excels at provisioning infrastructure across cloud providers like AWS, Azure, Google Cloud and so on. It uses a declarative approach—define the desired state in a configuration file, and Terraform makes it happen. Key features include:
- Multi-Cloud Support: Manage resources across various platforms so we can say that terraform is cloud-agnostic tools.
- State Management: Stores and tracks infrastructure state for accurate updates.
- Plan and Apply: Preview changes before execution to minimize risks.
- Syntax: Terraform uses HCL (Hashicorp Configuration Language) syntax
- Language: Terraform is declarative in nature which doesn’t matter in which sequence the code is written or the code cloud be scattered in multiple files and terraform is developed base on promise theory so that we define the desired state, terraform will make it happens for us.
- Life Cycle Management: Terraform supports life cycle management.
- Capabilities: Provisioning and Configuring. Even though terraform supports configuration management but it is not best practice to use to use for this use cases. For example: terraform provisioners can break idempotency concepts and terraform doesn’t know what you execute in the provisoners.
- Agentless: Terraform is an agentless
Ansible
Backed by Red Hat, Ansible shines in configuration management and application deployment. Its procedural nature executes tasks sequentially via simple YAML playbooks. Highlights include:
- Versatile Modules: Handles everything from system tweaks to cloud tasks.
- State Management: Ansible does not support state management.
- Syntax: Terraform uses YAML syntax
- Language: Ansible is procedural in nature- meaning when we write the playbook, the tasks will be performed in the sequence. For example: To install an Apache server on the given virtual machine, we have to write the task to install apache packages first before configuring and start the service.
- Life Cycle Management: Ansible does not support life cycle management.
- Capabilities: Provisioning and Configuring. Even though ansible supports provisioning the infrastructure but it not best practice to use for this use cases for following reasons.
- Ansible is lack of built-In state management
- Procedural Approach: To provision the infrastructure in ansible, we have to define every steps by steps which is a pain point in this use cases.
- Limited Multi-Cloud Support
- Scalability Challenges: Terraform is designed to scale efficiently, handling large and complex infrastructures with ease. Its ability to plan and apply changes in parallel speeds up provisioning. Ansible, however, executes tasks sequentially, which can slow down the process significantly when provisioning many resources. This makes Ansible less practical for large-scale infrastructure deployments.
- Agentless: Leverages SSH or WinRM, avoiding complex setups.
Using Terraform and Ansible Together
In practice, these tools complement each other:
- Terraform provisions the infrastructure—think VMs, networks, or databases.
- Ansible configures those resources, installing software and deploying applications.
By combining these tools together, it will enable an end-to-end approach to infrastructure automation as code