Terraform multi-account and multi-user AWS Template

The goal of this template is to create universal modules that can be used multiple times for the AWS infrastructure with multiple environments. These modules can be found inside the modules directory. In addition, the Terraform state can be managed centrally for each environment using the remote backend (S3).

• Create modules within the modules directory
• Call the module within the infrastructure directory
• Add environments .tfvars-file located in env_vars
• Manage AWS infrastructure by multiple users through remote backend

Disclaimer

This template was created in collaboration with Jan Degen and with help of publicly accessible platforms such a terraform.io and stackoverflow.

Prerequisites

You should have at least two AWS accounts.

Create AWS Roles in each of environment which have deployment privileges to deploy in their respective accounts. These roles must have account's AWS ID as their trusted entity.

• "arn:aws:iam:::role/Terraform"

Initial setup

Please note, that the initial setup should only be done the first time the structure is being setup on the AWS account. Once this setup has been completed, it is not necessary to repeat the initial setup.

After you have setup the backend, you can start with the creation and deployments of the infrastructure. All resources that should be created only on the account.

Setup AWS

Setup all AWS profiles in .aws/config and .aws/credentials

Init provider for remote backend

Go to /terraform-aws-template/terraform/remote-backend/provider.tf and add following attributes:

• AWS region
• profile name of you account
• role arn of you account

Init remote backend

• run following commands:
  • cd /terraform-aws-template/terraform/remote-backend
  • terraform init
  • terraform apply
• Copy the output generated as part of terraform apply into a file named backend-config.hcl and save it in /terraform-aws-template/terraform/infrastructure. This file will act as backend configuration for rest of your infrastructure.
• Add profile name from .aws/credentials for you account in backend-config.hcl.

Init remote backend config and environments

• run following commands:
  • cd /terraform-aws-template/terraform/infrastructure
  • terraform init -backend-config=backend-config.hcl
  • terraform workspace new

Init environment variables

go to /terraform-aws-template/terraform/infrastructure/env_vars and add to .tfvars all project and environments required variables

Deployment

The process for deploying infrastructure for all accounts is the same.

• cd /terraform-aws-template/terraform/infrastructure
• terraform workspace select
• terraform plan -var-file=".tfvars"
• terraform apply -var-file=".tfvars"

Module 00_generic

This module contains AWS Services that are required repeatedly when creating other modules.

random.tf

With the help of random class, a four-digit alphanumeric string is generated for the unique identifier of the AWS Services that created via Terraform.