OpenVPN with Terraform and Ansible on AWS

This repository is an example of an Infrastructure as Code devOps project. It provides fully automatic deployment of a private VPN on your AWS account using Terraform and Ansible.

Prerequisites

1) Install AWS CLI

• On MacOS: brew install awscli

For other Operating Systems see https://docs.aws.amazon.com/cli/latest/userguide/installing.html

2) Configure an admin user

1. Go to https://console.aws.amazon.com/iam/home#/home
2. Choose a username (e.g. terraform-vpn) and give programmatic access.
3. Add exiting policy: AdministratorAccess
4. Download the credentials and configure a profile in aws-cli

aws configure --profile terraform-vpn
aws iam get-user --profile terraform-vpn

3) Create a ssh key-pair to access the OpenVPN instance

ssh-keygen -t rsa -C "[email protected]" -b 4096 `
chmod 600 ~/.ssh/vpn

Configuration

1) Modify the config file as you wish /config.json

{
  "REGION": "eu-west-1",
  "PROFILE": "terraform-vpn",

  "VPN_INSTANCE_TYPE": "t3.micro",
  "VPN_AMI": "ami-00035f41c82244dab",
  "VPN_SSH_PUBLIC_KEY": "~/.ssh/vpn.pub",
  "VPN_SSH_PRIVATE_KEY": "~/.ssh/vpn",
  "OVPN_PORT": "1194",

  "VPC_CIDR": "172.20.0.0/16",
  "VPC_CIDRS": {
    "public": "172.20.3.0/24",
    "private": "172.20.1.0/24"
  }
}

2) Modify the default vars of the openvpn ansible role as you wish /ansible/roles/openvpn/default/main.yml

ovpn_cidr: 10.3.0.0/24
ovpn_network: 10.3.0.0 255.255.255.0
ovpn_push_routes:
  - 172.20.0.0 255.255.0.0

ca_dir: /home/ubuntu/ca

ca_key_country: BE
ca_key_province: BR
ca_key_city: Brussels
ca_key_org: MyOrganization
ca_key_email: [email protected]
ca_key_org_unit: MyOrganizationalUnit
ca_key_name: vpn_server

Setup

1) Add the AWS credentials to your environment

export AWS_ACCESS_KEY_ID="YOUR_AWS_KEY_ID"
export AWS_SECRET_ACCESS_KEY="YOUR_AWS_SECRET"
export AWS_DEFAULT_REGION="YOUR_AWS_REGION"

2) Bootstrap the infrastructure

cd terraform
terraform init
terraform plan --var-file ../config.json
terraform apply --var-file ../config.json

3) Wait till the EC2 is ready

4) Install OpenVPN on the EC2 Instance

This will download a zip file with client openvpn configuration and keys to your host.

cd ansible

# This will also add a client
ansible-playbook -i inventory openvpn_install.yml -e "username=john" -e "output=/tmp/john_vpn.zip"

4) Add an additional client to the VPN

This will download a zip file with client openvpn configuration and keys to your host.

cd ansible
ansible-playbook -i inventory openvpn_add_client.yml -e "username=john" -e "output=/tmp/john_vpn.zip"

Reprovision the EC2

If you want to recreate the vpn server with a new IP adress and new correct configuration, run these commands:

# taint the ec2 instance and ansible inventory generation script, this means it will be destroyed and recreated

cd terraform
terraform taint aws_instance.vpn
terraform apply --var-file ../config.json -auto-approve

# wait till the instance get up ...

# provision again with ansible
cd ../ansible
ansible-playbook -i inventory openvpn_install.yml -e "username=john" -e "output=/Users/brmm/Desktop/john_vpn.zip"

DNS Problems:

• If you use tunnelblick on Mac on Sierra or higher you might have DNS issues with allowChangesToManuallySetNetworkSettings see this github issue