KB2803748 Failover Cluster Management snap-in crashes after you install update 2750149 on a Windows Server 2012-based failover cluster

When you install KB2750149 (An update is available for the .NET Framework 4.5 in Windows 8, Windows RT and Windows Server 2012) you’ll have an issue with the Cluster GUI.image

Basically it shows an error message. The issue caused by installing the above update 2750149 on a Windows Server 2012-based failover cluster or a management station running the Failover Cluster Management snap-in. In this situation, the Failover Cluster Management snap-in crashes. Do NOT worry, the entire cluster is fine, this is just a GUI bug that will leave your GUI work/results pane blank after closing the error screen and basically unusable.


The only known workaround was to uninstall the hotfix or not install it at all on any node where you need to use the Cluster GUI (Windows 8 with RSAT for example). But now there is a fix released with KB2803748.

The update requires no reboot unless you have the Cluster GUI running as that it locks the file that need replacing. So keep them closed and you’re good to go. Also, it’s also great opportunity to use Cluster Aware Updating (CAU) with the hotfix plug-in to install the hotfix in an orchestrated fashion.

UPDATE: This update is also available now via WSUS. So updating is possible via the CAU windows update plug-in Smile


Failover Cluster Node Names in Upper & Lower Case In Window 2012 with Cluster.exe, PowerShell & GUI


Cluster Node Names Can Be Inconsistently Named

A lot of us who build failover clusters are bound to run into the fact that the node names as shown the Failover Cluster Management GUI is not always consistent in the names format  it gives to the nodes. Sometimes they are lower case, sometimes they are upper case. See the example below of a Windows Server 2008 R2 SP1 cluster.


Many a system administrator has some slight neurotic tendencies. And he or she can’t stand this. I’ve seen people do crazy things like trying to fix this up to renaming a node in the registry. Do NOT do that. You’ll break that host. People check whether the computer object in AD is lower or upper case, whether the host name is lower or upper case, check how the node are registered in DNS etc. They try to keep ‘m all in sync at sometimes high cost Smile But in the end you can never be sure that all nodes will have the same case using the GUI.

So what can you do?

  1. Use cluster.exe to add the node to the cluster. That enforces the case you type in the name!  An example of this is when you’d like upper case node names:
    cluster.exe /cluster:CLUSTER-NAME /add /node:UPPERCASENODE1
  2. Some claim that when you add all nodes at the same time and they will all be the same. But ‘m not to sure this will always work.

Windows 2012

In Windows 2012 PowerShell replaces cluster.exe (it is still there, for backward compatibility but for how long?) and they don’t seem to enforce the case of the names of the node. For more info on Failover Clustering PowerShell look at Failover Clusters Cmdlets in Windows PowerShell, it’s a good starting point.

Don’t despair my fellow IT Pros. Learn to accept that fail over clustering is case insensitive and you’ll never run into any issue. Let it go …. Well unless you get a GUI bug like we had with Exchange 2010 SP1 or any other kind of bug that has issues with the case of the nodes Smile.

If you want to use cluster.exe (or MSClus) for that matter you’ll need to add it via the Add Roles and Features Wizard / Remote Administration Tools /Feature Administration Tools / Failover Clustering Tools. Note that there are not present by default.



On an upgraded node I needed to uninstall failover clustering and reinstall it to get it to works, so even in that scenario they are gone and I needed to add them again.

MSClus and Cluster.EXE support Windows Server 2012, Windows 2008 R2 and Windows 2008 clusters. The Windows Server 2012 PowerShell module for clustering supports Windows Server 2012 and Windows Server 2008 R2, not Windows Server 2008.

For more information see the relevant section at Remote Server Administration Tools (RSAT) for Windows Vista, Windows 7, Windows 8 Consumer Preview, Windows Server 2008, Windows Server 2008 R2, and Windows Server “8” Beta (dsforum2wiki). You’ll have to live with the fact that a lot of documentation still refers to Windows Server 8. As of his post, it’s only been a week that the final name of Windows Server 2012 was announced.



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Upgrading Hyper-V Cluster Nodes to Windows Server 2012 (Beta) – Part 3

This is a multipart series based on some lab test & work I did.

  1. Part 1 Upgrading Hyper-V Cluster Nodes to Windows Server 2012 (Beta) – Part 1
  2. Part 2 Upgrading Hyper-V Cluster Nodes to Windows Server 2012 (Beta) – Part 2
  3. Part 3 Upgrading Hyper-V Cluster Nodes to Windows Server 2012 (Beta) – Part 3

And we have arrived at part three of my adventures while “transitioning” my Hyper-V cluster nodes to Windows Server 2012. I prefer the term transition as is more correct. We can still not do a rolling upgrade a cluster cluster. We still need to create a new cluster and recuperate the evicted nodes.

I’ll repeat myself here (again) by stating I did not reinstall the evicted nodes but upgraded them. Why, because I can and I wanted to try it out and see what happens. For production purposes I do advise you to rebuild nodes from scratch using a well defined and automated plan if possible. I already mentioned this in Upgrading Hyper-V Cluster Nodes to Windows Server 2012 (Beta) – Part 1

Moving the Storage & Hyper-V Guests

So we stopped Part 2 at a newly created cluster without any storage. That’s what we’ll be taking care of in this part.  Let’s recap what we already mentioned at the end of Part 2.

We have several options for storage here. We could assign new storage but we cannot do a Quick Storage Migration between cluster using SCVMM2008R2 but that doesn’t fly as SCVMM2008R2 can’t manage Windows 2012 clusters and I don’t know if it ever will. We can do a good old manual or scripted export to and import from the new storage of the VMs what takes a considerable amount of time. You also need to have the extra storage available.

We can also recuperate the old storage with the VMs still on there. This could get tricky as no two cluster should be able to see & use the storage at the same time. The benefit could be that we can just use the import type in Windows Server 2012 “Register the virtual machine in-place” (use the existing unique ID) and be done with it. We’ll try that one. We’ll still have some down time but it should be pretty fast. It’s only from Windows Server 2012 on that we’ll be able to do Shared Nothing Live Migrations between clusters Smile and live will be good. If you have a SAN you could also use clones to get this job done without less risk. You work on cloned data and keep the original around instead of using that for the process described below.

So how do we approach this?

Since Windows Server 2008 storage & clustering isn’t the pain it could be in earlier version. It’s the disk manager handling all that and it makes live a lot easier. All disks presented to a cluster node are off line to the operating system until you bring it online. Even if it contains data or is presented to another host, whether that is a member of another cluster or a stand alone host. Pretty cool. It also means you can have all your nodes on line during the process. The process of bringing the disk online and, if needed formatting it with NTFS and then adding it to the cluster as storage can be done on just one of the nodes.

As you recall I unplugged the evicted node from the iSCSI storage (you could also disable the ports) before I upgraded it. The entire iSCSI configuration got upgraded perfectly so all I needed to do was plug the iSCSI cables in and the storage appeared offline. My old cluster node was up and running still accessing it. Pretty slick! And great as a demo but you can play it safer. That was fun Smile but perhaps we won’t be that brave in a production environment.


You could decide to bring all LUNS over at once or one at the time. The process is the same. If you do it one by one you’ll have to rely on the above behavior to protect the LUNs against corruption or you can un-present the LUNS remaining on the old cluster from the new cluster so you’ll never have an issue. We’ve done both and it works out rather fine in testing. Windows clustering is really doing it’s best to prevent you from shooting yourself in the foot Smile

Let’s say I go LUN by LUN. Now I can just remove the VMs from the old cluster using the Failover cluster GUI so they are no longer highly available on that node. When I have no more clustered VMs on a CSV LUN I can shut down all the guests in Hyper-V Manager and stop right there.

On the old cluster I remove that LUN from the CSV storage and from the cluster storage. At that moment that LUN is already taken offline for you!


Pardon the silly size but I didn’t have space left to make a realistic screenshot Smile

Great, Windows is protecting us against any possible data corruption! So now I can than un-present the LUN form the old cluster nodes. The next step is to enable the ISCI ports, present that LUN to the new cluster node or nodes (depends on where in the x number of node process you are) or just plug in the cable .

You’ll see the new LUN off line than on the new cluster. We can than make the LUN on line so it will be available to add to the cluster. Just right click that disk and select “Online”.




Right click on storage



Select an disk that’s available to add to the cluster.



Things has gotten a lot simpler with CSV in Windows Server 2012. No more enabling it with a funky warning message that’s well meant but is rather confusing an annoying. You just right click the disk and choose “Add to Cluster Shared Volumes” and that’s it.



And there it is. That disk in our new cluster is ready to use as a CSV.



So we can now us a nifty new capability in Windows Server 2012 Hyper-V: “Register the virtual machine in-place” (use the existing unique ID)



The wizard starts.



Select the folder where your VM or VMs live. yes you can do multiple given that your folder structure allows for this.



It’s found one VM in our folder



We click Next



We select “Register the virtual machine in-place” (use the existing unique ID) and click next.


If something is not right like some forgotten “saved” states you’ll get a change to dump those or cancel the process to deal with it properly before trying it again.



If virtual network names do not match you’ll get the opportunity to set correct that by specifying what virtual switch to use.



If all was well in the first place or after you’ve fixed any issues like the ones demonstrated above you’re good to go. Click finish and enjoy your Windows Server 2012 Hyper-V Guest.



At this point you can already start your VMs. I know that the next step is to make all these VMs highly available but here we have some good news as well. You can now make running VMs highly available. Yeah! They no longer need to be shut down. All this is done via the well know process so I’m not going to walk trough the entire process here. But the screen shot of a making a running VM highly available is worth posting Smile


KB Article 2522766 & KB Article 2135160 Published Today

At this moment in time I don’t have any more Hyper-V clusters to support that are below Windows Server 2008 R2 SP1. That’s good as I only have one list of patches to keep up to date for my own use. As for you guys still taking care of Windows 2008 R2 RTM Hyper-V cluster you might want to take a look at KN article 2135160 FIX: "0x0000009E" Stop error when you host Hyper-V virtual machines in a Windows Server 2008 R2-based failover cluster that was released today. The issue however is (yet again) an underlying C-State issue that already has been fixed in relation to another issue published as KB article 983460 Startup takes a long time on a Windows 7 or Windows Server 2008 R2-based computer that has an Intel Nehalem-EX CPU installed.

And for both Windows Server 2008 R2 RTM and SP1 you might take a look at an MPIO issue that was also published today (you are running Hyper-V on a cluster and your are using MPIO for redundant storage access I bet) KB article 2522766 The MPIO driver fails over all paths incorrectly when a transient single failure occurs in Windows Server 2008 or in Windows Server 2008 R2

It’s time I add a page to this blog for all the fixes related to Hyper-V and Failover Clustering with Windows Server 2008 R2 SP1 for my own reference Smile