Building out Azure Container Registry in Terraform

So I’ve previously done posts on the TerraForm template that I built to support creating a kubernetes cluster. The intention behind this was to provide a solution for standing up a kubernetes cluster in Azure Government. To see more information on that cluster I have a blog post here.

Now one of the questions I did get with it, is “How do we integrate this with Azure Container Registry?” And for those not familiar, Azure Container Registry is a PaaS offering that Azure provides that allows you to push your container images to a docker registry and not have to manage the underlying VM, patching, updates, and other maintenance. This allows you to just pay for the space to store the container images, which admittedly are very small.

The first part of implementing this logic was to create the Container Registry in TerraForm by using the following.

A key note is that the use of the “count” variable is to enable that this registry will not be created unless you create a “lkma” which is the VM that operates as the master.

resource "azurerm_container_registry" "container-registry" {
  count = "${lookup(var.instance_counts, "lkma", 0) == 0 ? 0 : 1}"
  name                = "containerRegistry1"
  resource_group_name = "${azurerm_resource_group.management.name}"
  location            = "${var.azure_location}"
  admin_enabled       = true
  sku                 = "Standard"

  depends_on = ["azurerm_role_assignment.kub-ad-sp-ra-kv1"]
}

So honestly didn’t require that much in the way of work. For the next part it is literally just adding a few lines of code to enable the connection between the registry and the kubernetes cluster. Those lines are the following :

echo 'Configure ACR registry for Kubernetes cluster'
kubectl create secret docker-registry <SECRET_NAME> --docker-server $5 --docker-email $6 --docker-username=$7 --docker-password $8
echo 'Script Completed'

So really that is about it. I’ve already made these changes to the GitHub template, so please check it out. The above lines of code allow a user principal information that I pass to the script to be used to connect the azure container registry to my cluster. That’s really about it.

TerraForm Kubernetes Template

Hello All, I wanted to get a quick blog post out here based on something that I worked on, and finally is seeing the light of day.  I’ve been doing a lot of work with TerraForm, and one of the use cases I found was standing up a Kubernetes cluster.  And specifically I’ve been working with Azure Government, which does not have AKS available.  So how can I build a kubernetes cluster and minimize the lift of creating a cluster and then make it easy to add nodes to the cluster.  So the end result of that goal is here.

Below is a description of the project, and if you’d like to contribute please do, I have some ideas for phase 2 of this that I’m going to build out but I’d love to see what others come up with.

Intention:

The purpose of this template is to provide an easy-to-use approach to using an Infrastructure-as-a-service deployment to deploy a kubernetes cluster on Microsoft Azure. The goal being that you can start fresh with a standardized approach and preconfigured master and worker nodes.

How it works?

This template create a master node, and as many worker nodes as you specify, and during creation will automatically execute the scripts required to join those nodes to the cluster. The benefit of this being that once your cluster is created, all that is required to add additional nodes is to increase the count of the “lkwn” vm type, and reapply the template. This will cause the newe VMs to be created and the cluster will start orchestrating them automatically.

This template can also be built into a CI/CD pipeline to automatically provision the kubernetes cluster prior to pushing pods to it.

This guide is designed to help you navigate the use of this template to standup and manage the infrastructure required by a kubernetes cluster on azure. You will find the following documentation to assist:

  • Configure Terraform Development Environment: This page provides details on how to setup your locale machine to leverage this template and do development using Terraform, Packer, and VSCode.
  • Use this template: This document walks you through how to leverage this template to build out your kubernetes environment.
  • Understanding the template: This page describs how to understand the Terraform Template being used and walks you through its structure.

Key Contributors!

A special thanks to the following people who contributed to this template:
Brandon Rohrer: who introduced me to this template structure and how it works, as well as assisted with optimizing the functionality provided by this template.