Azure Sensible

This repository provides a set of example, template Terraform and Ansible files for deploying and configuring Azure virtual machines.

Why might you want to use this

Through using and building upon these examples you will find that your deployment is

• 🚅 Fast (no forms or pointing and clicking in your browser required)
• 🔁 Reproducible (as long as you keep your configuration files you can tear down and redeploy your environment on demand)
• 🔐 Secure (public key authentication by default with optional two-factor authentication)
• 💻 Hackable (we aim to provide a good starting point for building the environment you need)
• 🤝 Permissively licensed (you are free to copy, use and modify this code as well as to merge it with your own)

What this is not

While we hope this repository will be useful it will not (and is not intended to) solve all cloud computing problems. In particular this template is not intended to expose all of the possibilities of Ansible and Terraform.

For more complicated architectures, such as those involving multiple hosts, it may be best to build your deployment from the ground up. Nevertheless, we hope that you can still find some inspiration and useful hints here.

How to use this repository

The repository is split into two directories terraform and ansible which contain the Terraform and Ansible files respectively. Terraform is used to deploy the Azure resources (virtual machines, disks, public IP address, etc.) and Ansible is used to configure the virtual machine.

🎁 Get the code

Download and unzip the latest release or clone this repository

$ git clone https://github.com/alan-turing-institute/azure-sensible.git

📦 Requirements

Before you start, you will need to install some dependencies,

• Azure CLI
• Terraform
• Ansible

Additionally for generating QR code images to be scanned with an authenticator app you will need,

• Python > 3.6
• qrencode (which you will likely be able to find on you distributions repositories or on brew)

🏞️ Terraform, provisioning your virtual machine

To use terraform to deploy infrastructure on Azure, you will first need to authenticate using the Azure CLI

$ az login

which will launch a browser prompting you to login.

Then you will need to enable the subscription you want to deploy the VM into. Terraform will use your enabled-by-default subscription.

$ az account set --subscription <Subscription Name or ID>

To see a list of subscriptions available to you, run: az account list --output table

Next you can configure your deployment by editing terraform/terraform.tfvars. This file has comments explaining the configuration options and their default values.

Initialise terraform

$ cd terraform $ terraform init

Plan your changes

$ terraform plan

this will print a list of changes to your terminal so you can see what terraform will do. Run the terraform plan with

$ terraform apply

⚠️ Warning

The Terraform plan generates an SSH key for the Ansible admin account. The private key is stored unencrypted in the Terraform state file. This is not a secure if you intend on sharing the terraform state and should be replaced if you intend on doing so.

⚙️ Ansible, configuring your virtual machine

Ansible uses an inventory file to declare managed nodes and arrange them into groups. The terraform plan will have created an inventory for you specifying your virtual machine and how to connect to it in the ansible directory.

Similarly to terraform, there is a variables file with some options regarding how Ansible will configure your virtual machine. Edit ansible/ansible_vars.yaml, as before there are comments to explain the options.

You can use scripts/generate_password.py to create compatible password hashes for your users without displaying the password as plain text. See the README for instructions.

Install the required ansible modules from Ansible Galaxy

$ cd ../ansible $ ansible-galaxy install -r requirements.yaml

Now run the playbook on the inventory generated by Terraform to configure your virtual machine

$ ansible-playbook -i inventory.yaml playbook.yaml

📱 Optional: generating QR code images

If the option totp was true in ansible_vars.yaml the Ansible play will have created a file in the ansible directory called totp_hashes.txt. This file contains the information needed to generate QR code images for each user.

To generate the QR code images run the included Python script

$ ./scripts/generate_qr_codes.py

There will now be a set of PNG files in your current directory, one for each user, with file names in the format <username>.png. These can be distributed to each user so that they may scan the QR code with their authenticator app.

🔗 Connect to your virtual machine

Both the Terraform plan and the Ansible playbook will finish by printing the public IPv4 address of your virtual machine. You can connect to the machine via SSH using this IP address and the credentials of a user your created

$ ssh <username>@<ip_address> -i <path_to_private_keyfile>

💣 Destroy the resources

When you are finished, you can destroy the resources using Terraform. From the terraform directory run

$ terraform destroy

This will delete all Azure resources and any data stored on these resources will be lost.

Next steps

See the examples directory README for some practical examples building on the base configuration files.