terraform-aws-ha-web-app

Description

Builds a highly available AWS infrastructure from Terraform for a php web application communicating with a database.

More informations here

Modules

name	usage
vpc	Creates VPC with two public subnets for your ELB and two private subnets for your EC2 instances and your RDS service on different AZs
alb_asg	Creates an Auto Scaling group with ELB of type "application"
cloudwatch_cpu_alarms	Creates a cloudwatch alarms depending on the CPU usage and triggering ASG operations
s3	Creates an S3 bucket on which the sources of your application will be put
ec2_role_allow_s3	Creates an instance profile using an iam role authorizing access to S3 from your EC2 instances
rds	Creates a mariadb relational database used for our EC2 web instances

How it works

To use this project, you must first indicate the root password of our database. In my case, I chose to define it in a file called terraform.tfvars (this file name is automatically considered by Terraform during the execution of your configuration). Example :

db_password = "your-password"

Second, you must then create your ssh key pair in the keys folder. In my case, I use the ssh-keygen command as follows :

ssh-keygen -t rsa

Generating public/private rsa key pair.
Enter file in which to save the key (/home/hatim/.ssh/id_rsa): ./keys/terraform
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 

Then add the path of your public key in your root module in the path_to_public_key parameter of the my_alb_asg module. In my case it will be :

module "my_alb_asg" {
    ...
    ...
    path_to_public_key   = "/home/hatim/Documents/tmp/terraform/sources/keys/terraform.pub"
    ...
    ...
}

You can then launch your configuration with the following command

terraform init && terraform apply

Result :

...
...

Outputs:

alb_dns_name = [DNS OF YOUR ELB] 

Finally open your browser and test your application from the dns name of your ELB :