CI/CD with Kubernetes on ACS - Part 2 - Creating ACS and ACR

Part 1 - Introduction
Part 2 - Creating ACS & ACR (this post)
Part 3 - Configuring VSTS Part 4 - Kubernetes-ifying Application
Part 5 - Build Definition
Part 6 - Release Definition
Part 7 - Wrap-up

Install Azure CLI

The first step is to get up and running with Azure and the Azure CLI. You can get a free trial for Azure here, which will give you more than enough credit to get started. If you already have an Azure subscription, make sure that you have the necessary permissions to create Service Principals as this is required by Kubernetes for configuring the Azure resources.

You can get the Azure CLI v2 from here.

Once you are set up with an Azure account and the CLI, open up a terminal/command prompt and run:

az login

This will prompt you with a code, and you will need to open a web browser to, enter the code, and login to your Azure account. Once this is complete, you will then be authenticated from the CLI.

Alternatively, depending on your account security settings, you can login using:

az login -u <username> -p <password>

Create the ACS Cluster

Next step is to create a new Resource Group in Azure to contain all of the resources we are going to be creating:

az group create --name k8scicd --location westeurope

Note: I’m using West Europe for everything as part of this series, as it contains all of the services that are required. Double check the Azure services by region page to help choose a suitable region for you.

Now we have our Resource Group, it’s time to create our Azure Container Service (ACS) cluster:

az acs create  --name k8scicd --resource-group k8scicd  --orchestrator-type kubernetes --dns-prefix bhk8s --verbose

This command creates the ACS cluster using k8s as the orchestrator and configures the DNS prefix for connecting to the cluster later; this DNS prefix must be unique as it is associated with some public IPs.

Once the cluster has been created, you’ll need to install kubectl, which is the CLI for k8s. You can do that by running the following:

sudo az acs kubernetes install-cli

This installs kubectl to /usr/local/bin/kubectl by default, but you can change it with the –install-location parameter if required.

To check that your k8s cluster is working, run:

kubectl get nodes

Assuming everything has gone to plan, you should get a list back of the nodes in your ACS cluster.

I’ll be honest: when I was writing this up, this command failed for me with the warning “Private key file is encrypted”. After a bit of troubleshooting, I worked out that it was because I had an old k8s config file lurking around that was trying to connect me to a different cluster.

To resolve this, I removed the existing config and then copied the new config down from my k8s cluster:

rm ~/.kube/config
scp $HOME/.kube/config

You now have a k8s cluster up and running!

Create the ACR

Before we move on, let’s set up our Azure Container Registry (ACR). To do this, we create a storage account, and than an ACR:

az storage account create --name bhacrstg --location westeurope --resource-group k8scicd --sku Standard_LRS
az acr create --name bhacr --location westeurope --resource-group k8scicd --storage-account-name bhacrstg

Another command, another error: this time it was “The subscription is not registered to use namespace ‘Microsoft.ContainerRegistry’”. As ACR has only recently become Generally Available, your subscription might not have been updated to register with the Resource Provider that supports it. Easily solved though:

az provider register --namespace Microsoft.ContainerRegistry
az provider show --namespace Microsoft.ContainerRegistry | grep registrationState

registrationState should change to “registered” when complete, which might take a couple of minutes.

Finally, we need to be able to push and pull container images from our ACR. To do this, we need a new Service Principal:

az ad sp create-for-rbac --scopes /subscriptions/<subcription_id>/resourcegroups/k8scicd/providers/Microsoft.ContainerRegistry/registries/bhacr --role Owner --password <password>

Note down the appID and name that are generated by this command as we will need them in the next step, which is adding these credentials to k8s:

kubectl create secret docker-registry bhacr --docker-server=https://<ACR_name> --docker-username=<appID> --docker-password=<password> --docker-email=<any_email>

Make sure you remember these settings as we will use them again as (spoliers!) part of the build definition in VSTS.

Now that you’re up and running with ACS & ACR, check out Part 3 to prepare VSTS.