Crying Cloud

Hands on with Azure Arc enabled data services on AKS HCI - part 1

As I’ve been deploying and testing AKS on Azure Stack HCI, I wanted to test the deployment and management of Azure Arc enabled data services running on one of my clusters.

This post is part one of a series that documents what I did to setup the tools and deploy a data controller. In other posts, I’ll detail deploying a PostgreSQL instance and how to upload metrics and usage data to Azure.

  • Part 1 discusses installation of the tools required to deploy and manage the data controller.

  • Part 2 describes how to deploy and manage a PostgreSQL hyperscale instance.

  • Part 3 describes how we can monitor our instances from Azure.

Hopefully it will give someone some insight into what’s involved to get you started.

First things first, I’ll make the assumption that you either have an Azure Stack HCI cluster with AKS running as that is the setup I have. If you have another K8s cluster, the steps should be easy enough to follow and adapt :) .

Install the tools

First things first, we need to set up the tools. As I’m on Windows 10, the instructions here are geared towards Windows, but I will link to the official documentation for other OS’.

  1. Install Azure Data CLI (azdata)
  1. Install Azure Data Studio
  1. Install Azure CLI

    • Install using the the following PowerShell command:
      Invoke-WebRequest -Uri https://aka.ms/installazurecliwindows -OutFile .\AzureCLI.msi; Start-Process msiexec.exe -Wait -ArgumentList '/I AzureCLI.msi /quiet'; rm .\AzureCLI.msi
    • Official documentation
  2. Install Kubernetes CLI (kubectl)

    • Install using the the following PowerShell command:
      Install-Script -Name 'install-kubectl' -Scope CurrentUser -Force
      install-kubectl.ps1 [-DownloadLocation <path>]
    • Official documentation

Once you’ve installed the tools above, go ahead and run Azure Data Studio - we need to install some additional extensions before we can go ahead and deploy a data controller.

Open the Extensions pane, and install Azure Arc and Azure Data CLI as per the screenshot below.

1.dataStudioExtensions.png

Deploying the data controller

Once the extensions are installed, you’re ready to deploy a data controller, which is required before you can deploy the PostgreSQL or SQL DB instances within your K8s cluster.

Open the Connections pane, click the ellipsis and select New Deployment:

2. createDC.png

From the new window, select Azure Arc data controller (preview) and then click Select.

3. createDC.png

This will bring up the Create Azure Arc data controller install steps. Step 1 is to choose the kubeconfig file for your cluster. If you’re running AKS HCI, check out my previous post on managing AKS HCI clusters from Windows 10; it includes the steps required to retrieve the kubeconfig files for your clusters.

Step 2 is where you choose the config profile. Make sure azure-arc-aks-hci is selected, then click Next.


5. createDC.png

Step 3 is where we specify which Azure Account, Subscription and Resource Group we want to associate the data controller with.

Within the Data controller details, I specified the ‘default’ values:

Parameter Value
Data controller namespace arc
Data controller name arc-dc
Storage Class default
Location East US

I’ve highlighted Storage class, as when selecting the dropdown, it is blank. I manually typed in default. This is a bug in the extension and causes an issue in a later step, but it can be fixed :)

I’ve highlighted the Storage class, as when selecting the dropdown, it is blank. I manually typed in default. This is a bug in the extension and causes an issue in a later step, but it can be fixed :)

Click Next to proceed.

Step 4 generates a Jupyter notebook with the generated scripts to deploy our data controller. If it’s the first time it has been run, then some pre-reqs are required. The first of these is to configure the Python Runtime.

I went with the defaults; click Next to install.

7. createDC.png

Once that’s in place, next is to install Jupyter. There are no options, just click on Install.

8. createDC.png

Once Jupyter has been deployed, try clicking Run all to see what happens. You’ll probably find it errors, like below:

I’ve highlighted the problem - the Pandas module is not present. This is simple enough to fix.

From within the notebook, click on the Manage Packages icon.

Go to Add new and type in pandas into the search box. Click on install to have Pip install it.

10. addextension.png

In the Tasks window, you’ll see when it has been successfully deployed

With the pandas module installed, try running the notebook again. You might find that you get another error pretty soon.

12. workbookerror.png

This time, the error indicates that there is a problem with the numpy module that’s installed. The issue is that on Windows, there is a problem with the latest implementation, so to get around it, choose an older version of the module.

Click on Manage Packages as we did when installing the pandas module.

Go to Add new and type in numpy into the search box. Select Package Version 1.18.5 . Click on install to have Pip install it.

13. numpy.png

You may also see some warnings regarding the version of pip, you can use the same method as above to get the latest version.

14. pip.png

OK, once all that is done, run the notebook again. I found that yet another error was thrown. Remember when I said there was a bug when setting the Storage Class? Well, it looks like even though I manually specified it as ‘default’ it didn’t set the variable, as can be seen in the output below.

The -sc parameter is not set. Not to worry, we can change this in the set variables section of the notebook:

arc_data_controller_storage_class = 'default'
16. fixvariable.png

And again, Run all again and when the Create Azure Arc Data Controller cell is run, you’ll notice in the output the parameter is correctly set this time around.

17. dcrunsuccess.png

From here on, there shouldn’t be any problems and the data controller deployment should complete successfully. Make a note of the data controller endpoint URL, as you’ll need this for the next step.

dmc@dmc-tech.co.uk

Connect to the Controller

Now that the data controller has been deployed, we need to connect to it from within ADC.
From the Connection pane, expand Azure Arc Controllers and click Connect Controller.

19. connectCont.png

Within the Connect to Existing Controller pane, enter the Controller URL recorded from the previous step, Name, Username and password that were specified when setting up the data controller.

20. connectCont.png

All being good, you’ll now see the entry in the connections pane.

21. connectCont.png

As you can see, there were a few things I had to workaround, but as this is a Preview product, it doesn’t bother me as it means I learn more about what is going on under the covers by getting it to work. I’m sure that by the time it is GA, the issues will be resolved.

Managing AKS HCI Clusters from your workstation

In this article, I’m going to show you how you can manage your minty fresh AKS HCI clusters that have been deployed by PowerShell, from your Windows workstation. It will detail what you need to do to obtain the various config files required to manage the clusters, as well as the tools (kubectl and helm).

I want to run this from a system that isn’t one the HCI cluster nodes, as I wanted to test a ‘real life’ scenario. I wouldn’t want to be installing tools like helm on production HCI servers, although it’s fine for kicking the tires.

Mainly I’m going to show how I’ve automated the installation of the tools, the onboarding process for the cluster to Azure Arc, and also deploying Container Insights, so the AKS HCI clusters can be monitored.

TL;DR - jump here to get the script and what configuration steps you need to do to run it

Here’s the high-level steps:

  • Install the Az PoSh modules

  • Connect to a HCI cluster node that has the AksHCI PoSh module deployed (where you ran the AKS HCI deployment from)

  • Copy the kubectl binary from the HCI node to your Win 10 system

  • Install Chocolatey (if not already installed)

  • Install Helm via Choco

  • Get the latest Container Insights deployment script

  • Get the config files for all the AKS HCI clusters deployed to the HCI cluster

  • Onboard the cluster to Arc if not already completed

  • Deploy the Container Insights solution to each of the clusters

Assumptions

  • connectivity to the Internet.

  • Steps 1 - 5 of the Arc for Kubernetes onboarding have taken place and the service principal has required access to carry out the deployment. Detailed instructions are here

  • You have already deployed one or more AKS HCI clusters.

Install the Az PoSh Modules

We use the Az module to run some checks that the cluster has been onboarded to Arc. The enable-monitoring.ps1 script requires these modules too.

Connect to a HCI Node that has the AksHci PowerShell module deployed

I’m making the assumption that you will have already deployed your AKS HCI cluster via PowerShell, so one of the HCI cluster nodes already has the latest version of the AksHci PoSh module installed. Follow the instructions here if you need guidance.

In the script I wrote, the remote session is stored as a variable and used throughout

Copy the kubectl binary from the HCI node to your Win 10 system

I make it easy on myself by copying the kubectl binary that’s installed as part of the AKS HCI deployment on the HCI cluster node. I use the stored session details to do this. I place it in a directory called c:\wssd on my workstation as it matches the AKS HCI deployment location.

Install Chocolatey

The recommended way to install Helm on Windows is via Chocolatey, per https://helm.sh/docs/intro/install/, hence the need to install Choco. You can manually install it via https://chocolatey.org/install.ps1, but my script does it for you.

Install Helm via Choco

Once Choco is installed, we can go and grab helm by running:

choco install kubernetes-helm -y

Get the latest Container Insights deployment script

Microsoft have provided a PowerShell script to enable monitoring of Arc managed K8s clusters here.

Full documentation on the steps are here.

Get the config files for all the AKS HCI clusters deployed to the HCI cluster

This is where we use the AksHci module to obtain the config files for the clusters we have deployed. First, we get a list of all the deployed AKS HCI clusters with this command:

get-akshcicluster

Then we iterate through those objects and get the config file so we can connect to the Kubernetes cluster using kubectl. Here’s the command:

get-akshcicredential -clustername $AksHciClustername

Onboard the cluster to Arc if not already completed

First, we check to see if the cluster is already onboarded to Arc. We construct the resource Id and then use the Get-AzResource command to check. If the resource doesn’t exist, then we use the Install-AksHciArcOnboarding cmdlet to get the cluster onboarded to our desired subscription, region and resource group.

$aksHciCluster = $aksCluster.Name
$azureArcClusterResourceId = "/subscriptions/$subscriptionId/resourceGroups/$resourceGroup/providers/Microsoft.Kubernetes/connectedClusters/$aksHciCluster"

#Onboard the cluster to Arc
$AzureArcClusterResource = Get-AzResource -ResourceId $azureArcClusterResourceId
if ($null -eq $AzureArcClusterResource) {        
            Invoke-Command -Session $session -ScriptBlock { Install-AksHciArcOnboarding -clustername $using:aksHciCluster -location $using:location -tenantId $using:tenant -subscriptionId $using:subscriptionId -resourceGroup $using:resourceGroup -clientId $using:appId -clientSecret $using:password }
            # Wait until the onboarding has completed...
            . $kubectl logs job/azure-arc-onboarding -n azure-arc-onboarding --follow
        }

Deploy the Container Insights solution to each of the clusters

Finally, we use the enable-monitoring.ps1 script with the necessary parameters to deploy the Container Insights solution to the Kubernetes cluster.

NOTE
At the time of developing the script, I found that I had to edit the veriosn of enable-monitoring.ps1 that was downloaded, as the helm chart version defined (2.7.8) was not available. I changed this to 2.7.7 and it worked.
The current version of the script script on GitHub is now set to 2.7.9, which works.
If you do find there are issues, it is worth trying a previous version, as I did.

You want to look for where the variable $mcrChartVersion is set (line 63 in the version I downloaded) and change to:

$mcrChartVersion = "2.7.7"

Putting It Together: The Script

With the high level steps described, go grab the script.

You’ll need to modify it once downloaded to match your environment. The variables you need to modify are listed below and are at the beginning of the script. (I didn’t get around to parameterizing it; go stand in the corner, Danny! :) )

$hcinode = '<hci-server-name>'
$resourceGroup = "<Your Arc Resource Group>"
$location = "<Region of resource>"
$subscriptionId = "<Azure Subscription ID>"
$appId = "<App ID of Service Principal>"
$password = "<Ap ID Secret>"
$tenant = "<Tenant ID for Service Principal>"

Hopefully it’s clear enough that you’ll need to have created a Service Principal in your Azure Sub, providing the App Id, Secret and Tenant Id. You also need to provide the Subscription of the Azure Sub you are connecting Arc to as well as the Resource Group name. If you’re manually creating a Service principal, make sure it has rights to the Resource Group (e.g. Contributor)

Reminder
Follow Steps 1 - 5 in the following doc to ensure the pre-reqs for Arc onboarding are in place. https://docs.microsoft.com/en-us/azure-stack/aks-hci/connect-to-arc

When the script is run, it will retrieve all the AKS HCI clusters you have deployed and check they are onboarded to Arc. If not , it will go ahead and do that. Then it will retrieve the kubeconfig file, store it locally and add the path to the file to the KUBECONFIG environment variable. Lastly, it will deploy the Container Insights monitoring solution.

Here is an example of the Arc onboarding logs

Here is an example of the Arc onboarding logs

and here is confirmation of successful deployment of the Container Insights for Containers solution to the cluster.What you will see in the Azure Portal for Arc managed K8s clusters:

and here is confirmation of successful deployment of the Container Insights for Containers solution to the cluster.

What you will see in the Azure Portal for Arc managed K8s clusters:

Before onboarding my AKS HCI clusters…

Before onboarding my AKS HCI clusters…

..and after

..and after

Here’s an example of what you will see in the Azure Portal when the Container Insights solution is deployed to the cluster, lots of great insights and information are surfaced:

On my local system, I can administer my clusters now using Kubectl and Helm. Here’s an example that shows that I have multiple clusters in my config and has specific contexts :

The config is derived from the KUBECTL environment variable. Note how the config files I retrieved are explicitly stated:

I’m sure that as AKS HCI matures, more elegant solutions to enable remote management and monitoring will be available, but in the meantime, I’m pretty pleased that I achieved what I set out to do.