Posts Taged azure-stack-hci

Azure Stack HCI details

Microsoft has announced a successor of the current Azure Stack HCI. The current solution is based on Windows Server 2019 using Hyper-V and Storage Spaces Direct. The new Azure Stack HCI solution is based on a new operating system originating from Windows Server 2019, called Azure Stack HCI. 

On our dedicated Azure Stack HCI page, we have explained what the solution is all about. In this blog, we’re diving a little deeper in the details.

Azure Stack HCI Operating System 

Azure Stack HCI is not only the name of the solution, but also the name of the Operating System. That means that Azure Stack HCI OS is breaking loose from Windows Server, and the (slow paced) release cadence. The Azure Stack HCI OS will be updates much more frequently like the SAC releases providing new features or improvements at a faster rate. 

As Azure Stack HCI is released before the upcoming version of Windows Server, we also get the announced enhancements sooner as expected. Such as;  

Full stack automatic updates

Firmware and drives updated through integration with Windows Admin Center. Automatic, no manual intervention needed.
See this screenshot from EMC Dell for the visuals, or take a look at their 7-min video here.

Storage rebuilds 75% faster

Azure Stack HCI includes a completely renewed Storage Spaces Direct repair mechanism! The cluster now tracks the changes in the data at a much finer granularity. This improves rebuild times up to 75%, narrowing maintenance windows further. 

Stretched clusters

Azure Stack HCI also provides us with the Stretched Clustering feature, build on top of Storage Replica. Using this new feature, we can span an Azure Stack HCI cluster over multiple sites providing business continuity and disaster recovery (BCDR) capabilities. 
Azure Stack HCI supports synchronous and A-synchronous replication. 

Affinity and Anti-Affinity

With the release of Azure Stack HCI there is a new feature included called ‘VM Affinity and Anti Affinity’.  


With Affinity rules you can achieve binding of two or more resources together. For example, you want your front-end webservers and back-end databases servers on the same physical location to avoid latency and increase performance. 


With Anti-Affinity, we achieve the exact opposite. 
If we want to distribute front-end webservers over multiple physical locations (fault domains) we can use Anti-Affinity rules. 
When one physical location is offline due to maintenance or unexpected failure, you make sure your application stays online. 

Windows Admin Center

With the release of Azure Stack HCI Microsoft also heavily invested again in Windows Admin Center. Windows Admin Center now includes cluster create options and with that several workflows to created different types of clusters like HCI, HCI+SDN and more.  
With these workflows we can setup the cluster completely using Windows Admin Center. Automation in the background makes sure the asked components are installed according to best-practices. 

Stripped down OS

Because Azure Stack HCI is intended for HCI clusters only, the OS it will be stripped down from unnecessary features. Meaning, many features that are currently part of the Window Server OS will not be available in the Azure Stack HCI OS… 
Current features and roles in Windows Server 2019: 268 
Current features and roles in Azure Stack HCI: 193 
For example, the Active Directory and related roles such as DNS, Certificate Services, Federation Services, DHCP and Print Services will not be included, and more features might follow.  
These features will still be available in the regular Window Server releases, just not in Azure Stack HCI.  

Azure Stack HCI Billing

Since Azure Stack HCI is a cloud solution, the billing model will change to a cloud billing model.

Traditional Windows Server licensing

With Windows Server there always has been a licensing model calculated per physical processor core. Depending on the number of physical processor cores in your server, a number of core-packs must be purchased.

Azure Stack HCI licensing

With Azure Stack HCI you are also licensed per physical processor core. The difference with Windows Server licensing is that there is no concept of core-packs, you pay for the amount of physical processor cores in your cluster.

With this model the licensing costs switches from a CAPEX to an OPEX model.
When Azure Stack HCI is down or up-scaled the day-to-day expenses change.

Because the billing is managed through Microsoft Azure we can leverage the tools available to get more insights on costs. For example, with Azure Cost Analyses we can query the information and provide forecasts. In addition, the Azure APIs can be used with third party tooling for cost management.

Guest operating systems not included

One important aspect to note is that guest operating systems are not included in the license, like with Windows Server 2019 Datacenter edition.
This means that you will need to license VMs running on the Azure Stack HCI solution.

Azure Connection required once per month

Because the billing runs through Microsoft Azure, the cluster must be registered to Microsoft Azure within 30 days after deployment. After registration the cluster needs to connect to Microsoft Azure once every 30 days to report cluster status. If the cluster is unable to report the cluster will be out of policy.


Support via Azure support tickets

As cloud solution, the support of Azure Stack HCI falls under the umbrella of Microsoft Azure support. That means that you could request support by going to and file a support request there for your Azure Stack HCI solution.


Azure Stack HCI resource provider

Microsoft has created a dedicated resource type in Azure Resource Manager for Azure Stack HCI clusters.

By registering Azure Stack HCI clusters to the resource provider in Microsoft Azure an Azure Resource is created that represents the cluster.


Self-service VMs through Azure Portal

Want to offer your users a consistent experience with Azure? You now can.
Azure Stack HCI makes use of the same toolset as Microsoft Azure, including the portal and ARM templates. Using Azure Resource Manager (ARM) you can also delegate access to users in your Azure AD.

Contact Splitbrain for more information

Unsure how the new Azure Stack HCI fits in your organization? Or what is going to happen to your existing Azure Stack HCI clusters based on Windows Server 2019?

Contact us, we’re happy to help you.

    Automatically Update Storage Spaces Direct (S2D) Clusters

    Windows Updates may seem as ordinary business or something that you will deal with when the time is there, bear with us for a moment to explain why automatic updates on Storage Spaces Direct are different.

    For a long time now, we all know that it’s important to update our servers regularly with the latest Windows Updates for several reasons. 

    • It improves security because all software contains security flaws. Those flaws can be exploited for the wrong reasons by the wrong people. The updates fix the known security issues.

    • In some cases, it may improve performance because after all data from the field may give insights and some bits or bytes were not working as efficient as planned.

    • The stability of your environment may also increase. Since bugs are reported and get fixed and released through Windows Updates.

    Not your regular set of servers

    There are lots of ways to update your servers. You could do nothing, and Windows Update will at some point install the updates and eventually reboot your server. You could use Group Policies to download updates from Microsoft and schedule installation and reboot times to fit the company update policy. Other tools like Windows Server Update Service (WSUS) with GPO’s, System Center Configuration Manager (SCCM), Azure Update Management, or other third-party tools can also help to update your servers in a more controlled, centralized, and efficient way. When we look at clusters, in this case specifically Hyperconverged Infrastructure clusters, most of these tools are not sufficient enough and you should avoid using them. These HCI servers are not your regular set of servers, they require special attention and procedures to update them.


    Not very time-efficient but you can do it manually. Before you start, first validate the cluster status is healthy, then put a node in maintenance mode, install updates, restart the node. When it’s back online, monitor and wait for the storage to synchronize. When done, you can resume the node in the cluster. Now you can continue with the second node and repeat the process for every node in the cluster. Updating one node and waiting for the storage synchronization could take anywhere between 10 minutes and several hours depending on the change rate and performance of the nodes. You can imagine that this can take up several nights or weekends of IT personnel that could be spent otherwise.

    Virtual Machine Manager

    System Center Virtual Machine Manager (SCVMM) can help with automatically updating your S2D clusters by automating the update procedure. This way IT personnel can use their time on other matters and human errors is brought to the minimum. Virtual Machine Manager has specific support for Storage Spaces Direct or Azure Stack HCI clusters and takes care of the updating, restarting, and monitoring the storage repair jobs for you. You only need to start it, sit back, and let Virtual Machine Manager take care of the rest.

    Cluster Aware Updating

    Where SCVMM is additional software you need to purchase or may already have purchased, Cluster Aware Updating (CAU) is a free tool embedded in every Windows System as a feature. CAU is also capable of dealing with S2D or Azure Stack HCI clusters. Just like VMM, CAU also automates the update procedures and is aware of storage synchronization jobs.
    Three benefits of using Cluster Aware Updating;

    1. CUA allows update scheduling to install updates on a specific day and time

    2. Ability to use pre/post scripts to perform custom (Powershell) actions before or after an update of a node.

    3. CUA is able to install drivers and firmware in the process.

    Azure Automation

    Azure Update Management is a new way of automating Windows Updates on your servers. These servers can run in Azure or in your own datacenter. As it is a cloud offer on Azure, Microsoft is heavily investing in this. But still today you should avoid Azure Automation Update Management to patch cluster nodes. As described earlier this tool is not aware of clustering or storage jobs and will threaten your nodes as single instances, and things can miserably wrong fast.

    VMM or CUA?

    That leaves us with two choices. VMM and CAU both have their pro’s and con’s, but they have one thing in common.. they both save you time.
    If you want to learn more about updating your Storage Spaces Direct or Azure Stack HCI cluster and the different tools that are available to use you could watch the “Automatically Update S2D Cluster” video (in Dutch for now). In about 20 minutes we talk in-depth about the different tools to update Storage Spaces Direct or Azure Stack HCI clusters and go through the pros and cons. We will demonstrate both update processes and tell you all you need to know! Access the video here!

    Free 20-minutes video on Automatically update Storage Spaces Direct Clusters (Dutch)
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