terragrunt-infrastucture-example

This is just one of many structures for using Terragrunt.

1. Prerequisites

1. Install terraform and terragrunt
2. Configure your AWS credentials using one of the supported authentication mechanisms.
3. Update the parameters in the root terragrunt.hcl, and in env.hcl for each account.

1-1. Install Terraform and Terragrunt

You can download it from the official website.

• Install Terraform
• Install Terragrunt

1-2. Configure AWS credentials (using IAM Role)

To summarize, we need to create two IAM roles.

First, you need to create a policy with create/delete/update permissions on resources per account.

For our purposes, we'll name this role "ExecutionRole".

Next, Your AWS user must have an IAM policy which grants permissions for interacting with DynamoDB and S3. It also includes permission to assume the ExecutionRole role.

You can see how you can create an IAM Role with minimal permissions here.

NOTE: Recommend using a Trust Relationship to securely use Roles

1-3. Update the parameters

Update the parameter values required by the *.hcl file.

2. Deploy the infrastructure

2-1. Deploy single module

1. Change directory into the resource to deploy folder (eg. cd /prod/us-east-1/ec2)
2. Run terragrunt plan to see the changes you're about to apply.
3. If there are no issues, run terragrunt apply.

2-2. Deploy all modules

1. Change directory into the account/region folder (eg. cd /prod, cd /prod/us-east-1)
2. Run terragrunt run-all plan to see the changes you're about to apply.
3. If there are no issues, run terragrunt run-all apply.