Integrating Terraform with Ansible

Estimated time: 23 minutes

Overview

Questions

• How do Terraform and Ansible work together?
• What information must Terraform output for Ansible to use?
• How can Ansible provision software on a server Terraform created?

Objectives

• Explain the division of responsibilities between Terraform and Ansible.
• Generate Terraform outputs for Ansible inventory.
• Run Ansible against a Terraform-created EC2 instance.
• Describe when to run Terraform again versus when to run Ansible.

Why Terraform + Ansible?

---

Terraform builds infrastructure.
Ansible configures what is on that infrastructure.

Think of it as:

• Terraform creates the EC2 instance, networking, storage, and access.
• Ansible installs Dataverse, Payara, PostgreSQL settings, and more.

What Terraform Must Output

---

Ansible needs:

• Public IP or DNS
  
• SSH username
  
• SSH key path

Example outputs:

SH

```hcl
output "instance_public_ip" {
  value = aws_instance.dataverse.public_ip
}

output "instance_public_dns" {
  value = aws_instance.dataverse.public_dns
}
```

Show them with:

BASH

terraform output

Creating a Simple Ansible Inventory

---

BASH

[dataverse]
ec2-1-2-3-4.us-west-2.compute.amazonaws.com

[dataverse:vars]
ansible_user=root
ansible_ssh_private_key_file=~/.ssh/dataverse-ansible.ed25519

Instructor Note

Have learners SSH manually into the instance before running Ansible.

Running an Ansible Playbook

---

ansible-playbook -i inventory.ini dataverse.yml

Ansible will:

1. Connect over SSH
2. Install packages
3. Configure services
4. Deploy Dataverse

Terraform is not needed again unless infrastructure changes.

When to Use Terraform vs Ansible

---

Task	Terraform	Ansible
Create or destroy EC2 instances	✅	❌
Install Dataverse	❌	✅
Configure Payara	❌	✅
Change instance type or disk size	✅	❌
Restart services / roll out config	❌	✅

Challenge

Exercise: Test Connectivity

BASH

ansible dataverse -i inventory.ini -m ping

Show me the solution

dataverse | SUCCESS => {
  "changed": false,
  "ping": "pong"
}

Key Points

• Terraform = infrastructure
• Ansible = configuration
• Terraform outputs feed into Ansible
• Use Terraform for servers and networking
• Use Ansible for app installation and updates