Danny McDermott 11/5/20 Danny McDermott 11/5/20

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

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:

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.

Danny McDermott 10/27/20 Danny McDermott 10/27/20

Deploying AKS HCI Gotchas

I’ve been testing AKS HCI for a couple of months now, and I’m really excited about it as a platform and the possibilities it unlocks.

In the course of my testing, I’ve encountered some problems and undocumented steps that need to be configured to unsure that when you deploy your cluster, you are more likely to have success. Here’s a list in no particular order:

I’ll try and add to the list as and when I come across other gotchas

Using the PowerShell module is more efficient than using Windows Admin Center

I’ve tested deployments using both WAC and the PowerShell module and I’ve found using the latter gives the more consistent experience.

When first setting up AKS on the HCI cluster via WAC, a number of binaries / agents / scripts / OS images are downloaded to a working directory on the system running WAC before being copied to a CSV on the cluster. If you restart the wizard for whatever reason, all the contents of this working directory are wiped and downloaded again. I’ve found that with WAC, all the possible K8s Linux images are downloaded (at approx. 4 - 4.5 GB per image):

As you can see above, the Windows image is even larger. You may not want to run Windows workloads at the moment, but you’ve got to get the image no matter what.

The PowerShell module is more efficient, as it only downloads the image you require at that time. You can also specify an image store directory for the images when deploying to a cluster. This directory is persistent, so if you need to re-run installations due to failures, at least the time taken to download the images is saved.

Make sure your HCI Cluster has the correct rights in AD

On a couple of occasions, I’ve come across issues which have been resolved by making sure that the Azure Stack HCI Cluster has been correctly configured within Active Directory. As the AKS HCI installer (both PowerShell and WAC based) creates a generic service on the cluster to run the ‘Cloud Agent’ which is required as part of the deployment, the cluster computer object needs the rights to create (and delete) Computer objects at least.

Here’s an example of an error I encountered when it wasn’t configured:

For anyone interested, this is how to configure AD to resolve the problem:

Open dsa.msc (Active Directory Users and Computers) as a user with rights to modify security on the OU that the cluster computer object is located in.

Make sure the ‘Advanced Features’ option is selected within the View menu, to expose the Security tab within the OU properties.

Navigate to the OU where the HCI Cluster computer object is located in (in the example above, it is in the default Computer OU). Right click and select Properties.

From the resultant window, click on the Security tab, then Advanced

Click on Add

Click on Add, then Select a principal (1). Make sure you add the Computer Object type (2), enter the name of the HCI Cluster in the object name, chcek it is valid and click OK (3).

Make sure that the Create and Delete Computer Objects permissions are selected and then click OK. on the open windows to assign the permission.

Currently, you can only run the PowerShell modules directly on a HCI Node

This is for awareness, but you must run the AKS HCI PowerShell modules on a HCI node, PowerShell remoting is not supported currently. So you will need to RDP to the server to do this.

Pre-create a WSSD directory on your CSV

For version 0.2.8 of the AksHci PowerShell Module, I found that the kube-config yaml file attempts to be stored in a directory called wssd on the CSV that you specify when setting the config (e.g. if you specify the following: Set-AksHciConfig -deploymentType MultiNode -wssdImageDir 'C:\ClusterStorage\Volume01\wssdImages' -cloudConfigLocation C:\ClusterStorage\Volume01\aks-clus01-config -vnetName Computeswitch, the install routine would attempt to store the kube-config file in C:\ClusterStorage\Volume01\wssd).

If the wssd directory does not exist prior to installation, the routine will error. To get around this, create the directory beforehand.

Running the command that throws the error shows more detail

Creating the WSSD dir and re-running the command fixes the problem

Matt Quickenden 9/9/20 Matt Quickenden 9/9/20

Grow Your Azure Knowledge (Free Training)

If you haven’t seen this deal, its worth signing up for the generous price of free!

Pluralsight and Microsoft have partnered up for a free subscription to some Microsoft Azure courses on Pluralsight. You can register at Pluralsight and get a free Subscription for Microsoft courses valid until September 2025!

https://www.pluralsight.com/partners/microsoft/azure

Enjoy growing your knowledge.

Danny McDermott 8/12/20 Danny McDermott 8/12/20

Azure Stack Hub Update 2005

Microsoft recently released Azure Stack Hub Update 2005 (release notes here), and it is quite a big update, so I felt it warranted a blog post for some of the things I noticed that aren’t detailed in the release notes.

The first thing I noticed running the update is that there are some cosmetic updates.

First of all, the title in the portal is now correctly reflects the name change to Azure STack Hub. The above pictures show the before and after update changes. Note that the Region management ‘globe’ icon has changed too.

Other icons have also been refreshed to match those in Azure:

I prefer the new look, FWIW.

When you run an operation that could block an update, you now get a warning in the Update Management blade:

As you can see in the picture above, the operation MAS Update is in progress, so updates can’t be installed whilst that is running - makes sense. It will block operations such as adding a node to a scale unit and secret rotation.

I like this feature and will stop operators starting an update when it has no chance of completing due to these other activities taking place. Another thing I like is the ability to click on the link and it will take you to the activity log showing what operations are underway that is causing the block.

One thing that did catch my eye was the ability to stop, shut down, and restart an infrastructure role instance from the admin portal has been removed. I’ll admit that I have used this capability on more than one occasion, but I guess the telemetry that the PG have been receiving have shown that his has caused more problems than fixed, so whilst it is frustrating, I can understand the reasons.

Pre-2005 Update - You can restart an instance

Post-2005 update - You can only start a stopped instance

Most of the other updates relate to under the hood improvements such as autonomous healing capability, so reducing the number of alerts. Also, the Storage service API version 2019-02-02 is now supported.

Danny McDermott 6/17/20 Danny McDermott 6/17/20

Rotating Event Hubs RP External Certificate on Azure Stack Hub

I have been testing the Event Hubs public preview release for Azure Stack Hub, looking at the install process and what kind of actions an Operator would need to do to keep things running. One of the important ones for me, are rotating secrets / certificates. If your certificates expire, you won’t be able to access the RP, hence the importance.

If you check the current documentation for rotating secrets , it is the generic instructions for rotating external certificates for the Azure Stack Hub Stamp. I expect that this will be corrected in the near future, but until then , how do you do go about it for the Public Preview?

Firstly, you need the latest version of the Azure Stack Hub PowerShell modules:

Then you need to connect to your Azure Stack Hub Admin environment. Use the steps detailed in the following article : https://docs.microsoft.com/en-us/azure-stack/operator/azure-stack-powershell-configure-admin?view=azs-2002

(Remember if using the Az Module to rename the Commands per https://docs.microsoft.com/en-us/azure-stack/operator/powershell-install-az-module?view=azs-2002#7-use-the-az-module)

Copy the Event Hubs pfx file to a local directory and run the following script (The example is using theAz module)t:

$ProductId = 'microsoft.eventhub'
$productVersion = (Get-AzsProductDeployment -ProductId microsoft.eventhub).properties.deployment.version
$PackageId = ('{0}.{1}' -f $ProductId, $productVersion)
$packageSecret = ((Get-AzsProductSecret -PackageId $PackageId).value.name).split('/')[2]
$certPath = 'C:\AzsCerts\EventHubs\cert.pfx'

$pfxPassword = (ConvertTo-SecureString '<pfxPassword>' -AsPlainText -Force)
Set-AzsProductSecret -PackageId $PackageId -SecretName $packageSecret -PfxFileName $certPath  -PfxPassword $pfxPassword -Force -Verbose

Invoke-AzsProductRotateSecretsAction -ProductId $ProductId

Modify the $certPath variable and <pfxPassword> to match what you have set and then run the script.

The process will take quite a long time to complete. Whilst the operation is taking place, you will receive the status of the command.

If you choose to stop the CmdLet/script, the process will continue in the background. You can check the status at anytime by running the following:

(Get-AzsProductDeployment -ProductId microsoft.eventhub).properties

You should see something like this when the process is still running:

… and when successfully finished:

Hope that helps until the official documentation is released!

Article updated 16 July 2020 with an updated method to obtain the secret name, provided by @kongou_ae - Thanks!

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