Tag: Server 2016

Quite Impressed With Microsoft’s Hyper-V

I realise I’ve not posted for a while, and I’ll try and atone for that going forward, I’ve been a busy server guy at work, but onto the good stuff.

I know Hyper-V, I’m not new to the existence of Hyper-V, but I’ve only ever briefly touched it in lab environments, until recently.

I had cause to do a number of small site deployments in the US on Hyper-V, my first choice being for a proper VMware setup with vCenter and a shared storage platform, but for one reason or another, my hand was forced and I had to go in guns blazing with Hyper-V, no shared storage and no Microsoft System Centre Virtual Machine Manager (SCVMM) either.
For those that haven’t looked at Server Core installs yet, firstly, why not? Secondly, please do, it’s a great feature of Windows Server for enterprise and business setups and something that Windows Server nerds everywhere should be doing more of.
I’m happy with PowerShell, so deployment wasn’t hard, that’s not to say I’m 100% au-fait with every set of cmdlets on offer and know the whole she-bang inside out, but it’s pretty easy to get going. Once the install was done and networking configured (loving the native NIC teaming since Server 2012), Hyper-V role installed and servers fully patched it was time to start actually configuring the thing. Again, Microsoft have made the whole thing fairly straightforward via the Hyper-V console and since I’m not a PowerShell martyr, I use it where things are easier but use the GUI where it makes sense for some things, I was happy to proceed in the GUI for some of the configs.

So, onto what I liked, the live migration with shared nothing is great, although something I know ESXi also has. The replication of a VM between hosts, and the ability for one of those replicas to effectively be powered on in an unplanned failover scenario is great and failed back when things are working as planned again. Ok, I know it’s not a full HA setup in the sense that it requires intervention for it to work, but it’s a step up from what you get with just ESXi without vCenter.
Hot-add of memory is now available in Hyper-V since the Server 2016 version, as well as hot-add of network adapters, which brings it a lot of the way towards VMware’s offering in terms of hot-add features. PowerShell Direct is amazing, the ability to have a PowerShell based session to a guest OS from the host regardless of networking or firewall is great.
Obviously there are some things missing from Hyper-V still, vCPU hot-add being one, but not one that I personally use too often. The HTML5 interface of the later iterations of VMware’s product is also great, no need for an installed application to manage the thing is always good news.

Hyper-V can easily suffice for small scale deployments and is well worth a look these days. In its current evolution, it’s a big leap from where it was in its Server 2008 days. As time goes by, there really is getting less and less between Hyper-V and ESXi, and that can only be good. No one benefits from a monopoly position, with the exception of the monopoly holder, so it’s good to have some healthy competition in the market and I look forward to seeing what Microsoft can do with the platform in the future.

Server 2016 & Windows 10 Start Menu Not Working

I’d been having some problems with the start menu in both Server 2016 and Windows 10 stopping working. Googling around revealed various posts and loads of the same advice on how to fix the problem. These included using the Deployment Image Servicing and Management tool with the /restorehealth switch;

DISM /Online /Cleanup-Image /RestoreHealth

Reinstalling all modern apps via PowerShell with the following command;

Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}

Creating a new user account and just using that, not an option if the problem affects all accounts on the machine. The only one of the options mentioned that did help was to re-install Windows, this left the start menu working. However as soon as I domain joined the machine again, it stopped working again after a restart. This led me to look at Group Policy as a potential culprit, and sure enough, moving the object to a separate OU and blocking all policy on it left the start menu working. After a long process of linking policies in one by one I came down to a very specific registry setting.

I’d set the ACLs on a specific registry subkey of HKLM, in this case it was HKLM\Software\Microsoft\RPC. These ACLs were missing one specific entry, namely APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES.
Adding this in with only read permissions and forcing a policy update brought the start menu immediately back to life. That ACL is one that has appeared in Server 2012 I think, but since that particular part of our policy predates 2012 that ACL wasn’t there. Oddly enough I’ve not seen this cause any problems with Server 2012/2012 R2/Windows 8/8.1, only with Server 2016 & Windows 10.

So the take away from this is to make sure if you restrict any registry ACLs, make sure you include read access for APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES.

If all this was helpful and worked for you, please drop a quick note in the comments.

Server 2012, 2012 R2 & 2016 Disable Or Remove Deduplication On A Volume

Update – 11/11/2020: I’ve added a link here to Microsoft’s updated Server 2016 documentation that details deduplication – Understanding Data Deduplication

I just thought I’d post about this, as it’s something I’ve come up against recently, how to disable deduplication on a volume on Server 2012, 2012 R2 or 2016 and inflate the data back to it’s original form. In this example, the volume in question is E:

So let’s start with step one;
DO NOT DISABLE DEDUPLICATION ON THE VOLUME
If you disable dedup on the volume first, you simply stop new data being processed, rather than rehydrating your already deduplicated data.

So with that in mind the, step two would be to run the following command in PowerShell;
Start-DedupJob -Type Unoptimization -Volume E: -Full

When that job has completed, which you can check with the Get-DedupJob
command, you’ll then find that deduplication has been disabled on the disk. Since there’s still the garbage collection job to run, we need to rather counter-intuitively turn dedup back on for the volume with the following command Enable-DedupVolume -Volume E:

Once this is done, the next step is to run the following command to start your garbage collection on the volume;
Start-DedupJob -Type GarbageCollection -Volume E: -Full

Finally, after that, the final step is to turn off dedup on the volume with the following command;
Disable-DedupVolume -Volume E:

And that should save you any unnecessary drama.

Note
When all this is done, the volume will still show in some places like server manager sat at 0% deduplication rate, which is fine, as we’ve turned it off. I would guess this is just a bug, but it seems once a volume has been touched by the deduplication processes, it never goes back to a blank value for dedup rate.