Using Terraform and Ansible to provision WordPress On AWS EC2

After learning about terraform and doing some projects with it. I wanted to learn how to integrate ansible with terraform so that Ansible can be used as a configuataion managemnt tool.

We have learned how to use terraform with userdata to deploy wordpress and also successfully tested Terraform with remote-exec and file proviosner instead of userdata. Now in this tutorial I am going to show, how can we use ansible in Terraform to configure the provisioned resources.

Terraform is Provisoned managment tool which can proviosion AWS EC2 and RDS for our webserving purpose and Ansible is configuration Management tool via which we can install WordPress and Install webserver in it.

For this tutorial , ansible should be installed in your local system. Since ansible cannot be directly installed on Windows device , you can use WSL2 for this purpose. For Linux system install Ansible directly in you system.

Ansible playbook will be first rendered by terraform so that it can populated database values into it and then Ansible will run rendered playbook using local-exec provisioner.

Prerequisites

1. Download Terraform

2. Install AWS CLI

3. Configure your AWS with aws configure commmand

4. Install Ansible

5. Install Git bash

AWS Resources

I am going to create an EC2 instance where WordPress will be installed and an RDS instance where MySQL database for WordPress will be provisioned.

We are going to use Terraform to automate cloud infrastructure (i.e create instances and security groups) and Ansible to install an apache server and WordPress.

We are going to create VPC under which we are going to create 3 subnets in three different Availability zone.

EC2 will be provisioned to public subnet and RDS will be installed to private subnet.

Terraform script workflow

Terraform will use AWS CLI to interact with AWS resources. After confirming correct credentials, terraform start creating resources according to the written TF script. Terraform creates resources in a parallel manner but if one resource depends upon another resource, Terraform makes sure that the initial resource is created first. For eg security group is created before creating the instance.

In this case, since the WordPress database depends upon the RDS endpoint, I use depends_on on EC2 resource script to avoid creating EC2 instances before RDS.

Process

Make sure terraform is installed and AWS credentials are properly configured.

Download and unzip terraform projects here

The project consists of the following files:

1. main_script.tf Terraform script defining all required resources
2. terraform.tfvars User values of varaiable used in the project
3. user.tfvars User defined Database password
4. playbook_test.yml Ansible playbook for AWS LInux 2
5. file/wp-config.php.j2 WordPress configuration file for WordPress
6. variables.tf Variables value for aws resources

Go to the directory where you unzipped the downloaded project. Use any IDE to edit the variable in terraform.tfvars file. Change WordPress database user password in user.tfvars file. You can change database entries and EC2 instance types. Make sure you have the correct ami id ( for AWS LINUX 2 ) for the region.

Open a command prompt and navigate to the project folder and

Run git clone https://github.com/devbhusal/terraform-ansible-wordpress.git

Go to the project folder cd terraform-ansible-wordpress

Initialize Terraform   terraform init to install the plugin.

Generate Keypair using       ssh-keygen -f mykey-pair  

To verify what resources will create run

terraform plan -var-file="user.tfvars"

To apply run terraform apply -var-file="user.tfvars"

The elastic IP address will be displayed after all resources have been created.

After successfull provisioning of AWS Resources,Using remote-exec and private key, EC2 instance will be connected via SSH. Yum will be updated and Python will be installed so that local ansible server can communicate with the provisoned EC2 . Once Installation is done ,Using local exec , Ansible playbook will be run against provisioned EC2. Once Installation is done ,You will be provided with Public Ip address of WebServer.

Type IP address in your favorite web browser to confirm WordPress is installed. You will be prompted with a select language installation page.



To destroy all resources created by Terraform run terraform destroy -var-file="user.tfvars"

Thank you for reading!

Follow devbhusal/terraform-ansible-wordpress (github.com)