Tag Archives: Hyper-V

Difference between Windows Client Hyper-V and Server Hyper-V

Windows 8 supports virtualization on the client OS to allow IT professionals and developers to use Hyper-V as a desktop operating system. If you are an IT Professional or developer that uses Windows Server as development operating environments, you should be excited about new client Hyper-V feature in Windows 8 and wonder what are some of the key differences and similarities between Windows 8 Hyper-V and Windows Server 2012 Hyper-V?

Here are the some of the key differences in Windows 8 Client Hyper-V from Windows Server 2012 Hyper-V:

  • No Hyper-V Replica
  • No Hyper-V Network Virtualization
  • No Virtual Machine Live Migration (Requires Failover Clustering only in Windows Server)
  • No Shared Nothing Live Migration
  • No SR-IOV (You need server class hardware; appropriate firmware, etc; you won’t find this on desktops)
  • No Failover Clustering (Client doesn’t include Failover Clustering)
  • No Virtual Fiber Channel
  • No RemoteFX GPU Hardware Acceleration ( which requires RDV only in Windows Server)
  • Second Level Address Translation (SLAT) HW required

And the commonalities between Windows 8 Hyper-V & Windows Server 2012 Hyper-V

  • Virtual Machines created with Client Hyper-V are 100% compatible with Server Hyper-V
  • Client Hyper-V offers the same VM scale as Server
    • Up to 64 virtual processes per VM
    • Up to 64TB per virtual disk ( vhdx format )
    • Up to 1 TB of memory per VM.
  • Live Storage Migration is included
  • Support VHD Storage on SMB3 file shares
  • 100% PowerShell/WMI compatibility in management from Client to Server.
  • Client Hyper-V offers the full rich, open and extensible Hyper-V virtual switch.
  • QoS, bandwidth management and other advanced virtual switch capabilities are in there

Install Hyper-V Manager on Windows 10

To remotely manage your Windows Server 2008 Hyper-V server from a windows 7 desktop, you need install RSAT (Remote Server Administrator Tool). This has been simplified in Windows 10. In Windows 10, Hyper-V management tool is built in, Hyper-V manager can be turned on via “Turn Windows features on or off” dialog directly without downloading RSAT.


However, Hyper-V manager in Windows 10 can’t manage can’t manage Hyper-V running on downlevel operation systems. If you connect using Hyper-V manager it would fail with following error:

This version of Hyper-V Manager cannot be used to manage server running Hyper-V in Windows Server 2008 or Windows Server 2008 R2

The only workaround so far is remote into a Windows 7/Windows Server 2008 R2 machine and run Hyper-V manager there.

Solution for Unresponsive Win8 Guest VMs

If you’re going to run Windows 8 or Windows Server 2012 in a virtual machine on Windows Server 2008 R2 Hyper-V, please install this hotfix patch http://support.microsoft.com/kb/2744129 on the Hyper-V host server,

Without applying this hotfix, you may experience one or more of the following issues:

  • The Windows 8/Server 2012 virtual machine becomes unresponsive.
  • The Windows Server 2008 R2 host server displays a stop error message and restarts automatically.

Update: the http://support.microsoft.com/kb/2744129.has been added to Windows Auto Update.

How to tell if your CPU Supports SLAT

SLAT-enabled processor is the requirement of Hyper-V RemoteFX feature which is introduced in Windows Server 2008 R2. It’s the requirement of Windows 8 client Hpyer-V feature as well.

For INTEL CPU models, following CPU models are SLAT-Capable

  • Server: E5500 or higher.
  • Desktop/Laptops: I3/I5/I7/I7-qm

There is a handy tool named CoreInfo from systeminternals that can check if your CPU is SLAT-Capable, it’s pretty easy to use:

  1. Download from http://technet.microsoft.com/en-us/sysinternals/cc835722
  2. Launch an elevated command prompt
  3. Run “CoreInfo.exe -v”

If you see EPT * Supports Intel extended page tables (SLAT) then you are good.


Following are copied from https://social.technet.microsoft.com/wiki/contents/articles/1401.hyper-v-list-of-slat-capable-cpus-for-hosts.aspx

Servers that support SLAT

  • Any AMD server CPU based on Barcelona or later architectures. Some early Barcelona editions didn't have RVI, but they're relatively rare. Check this AMD list.
  • Intel server processors numbered E5500 and higher.
  • Any Intel CPUs based on Nehalem, Westmere, or Sandybridge micro-architectures. (There may be exceptions, but I'm not aware of any.)

Desktops that support SLAT

  • Intel processors whose names start with 'i', e.g. i3, i5, i7, i9. (There may be exceptions, but I'm not aware of any.)
  • Any Intel CPUs based on Nehalem, Westmere, or Sandybridge micro-architectures. (There may be exceptions, but I'm not aware of any.)

Laptops that support SLAT

  • Lenovo T410, T510, W510, W520, T420s, T520, X201
  • Samsung 900x
  • Dell Precision M4600

Hyper-v Tip: Use windows key without fullscreen

When connect to a remote VM with hyper-v manager, I have to full screen to make Windows key. Personally I think Hyper-V should have a Windows key button in toolbar like "Ctrl+Alt+Delete" button.

Actually Hyper-v manager allows you to select where the Windows keys goes when you press it. Open up the Hyper-V Settings dialog from with the Hyper-V Manager and go to the keyboard setting, you will see 3 settings.


  1. Use on the physical computer
  2. Use on the virtual machine
  3. Use on the virtual machine only when running full-screen

The default one is #3. Once you change it to #2, you will be able to use Windows key inside VM without *full-screen* it.

You will find this helpful if you are connecting to a VM has Windows 8 Metro UI enabled. Without a windows key it’s hard to exit Metro style app and go back to start screen.

Using Hyper-V in Windows 8

In Steven Sinofsky’s this blog - Bringing Hyper-V to “Windows 8”. He talks about that Windows 8 will support virtualization on the "client" OS.  This is very helpful for developers as they typically have the need to setup additional test environment on their PC/Laptop.

Hardware Requirements

Hyper-V supports creation of both 32-bit and 64-bit operating systems in VMs. To run Client Hyper-V, your computer must:

  • Be running a 64-bit version of Windows 8.
  • Have a CPU that supports Second Level Address Translation (SLAT), To determine if your CPU supports SLAT, go to How to tell if your CPU Supports SLAT

Enabling Client Hyper-V

  1. In the Windows 8 Control Panel, tap or click Programs, and then tap or click Programs and Features.
  2. Tap or click Turn Windows features on or off.
  3. In the Windows Features dialog box, select the check boxes for the Hyper-V items that you want to install, and then tap or click OK. image
  4. Tap or click Close.

Note: You must restart your computer to complete the Hyper-V installation. After restarting the computer, you can use Hyper-V Manager or Windows PowerShell to create and manage VMs. You can also use VM Console to connect to VMs remotely.

Enabling Client Hyper-V with Command Line Tool

  • Use Windows PowerShell. At the Windows PowerShell prompt (using administrator credentials), type the following:

Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V

  • Use the Windows Command Prompt. At the Windows command prompt (using administrator credentials), type the following:

Dism /online /enable-feature /featurename:Microsoft-Hyper-V –All

What Isn’t Included in Client Hyper-V?

Difference between Windows 8 Client Hyper-V and Server Hyper-V

IDE/ATAPI Account does not have sufficient privilege to open attachment

You might get following error after you move or replace a virtual disk drive file of a hyper-v virtual machine.

An error occurred while attempting to start the selected virtual machine(s).

'TestVM' failed to start.
Microsoft Emulated IDE Controller (Instance ID
{83F8638B-8DCA-4152-9EDA-2CA8B33039B4}): Failed to Power on with Error 'General
access denied error'
IDE/ATAPI Account does not have sufficient privilege to open attachment
'D:VMTestVMTestVM.vhd. Error: ‘General access denied error'
Account does not have sufficient privilege to open attachment
'D:VMTestVMTestVM.vhd. Error: ‘General access denied error'

This is because the permissions on the new virtual hard drive (D:VMTestVMTestVM.vhd in this case) are incorrect. Here is the steps to fix this permission file.

  1. Open Hyper-V manager, Right click settings of the virtual machine
  2. Find the Virtual Hard Drive and choose "Remove".
  3. Re-add the same Virtual Hard Drive back to the machine.
  4. Now start the VM again, it should boot successfully.

Install Remote Server Administration Tools on Windows 7 SP1

Remote Server Administrator Tools (RSAT) is not compatible with Windows 7 SP1. If you install Remote Server Administration Tools on Windows 7 SP1 slipstreamed media, you will get following error.

The update is not applicable to your computer

That’s because current RSAT version only supports Windows 7 RTM. To workaround this issue, you can Install Remote Server Administration Tools before installing Windows 7 SP1. The SP1 upgrade will update RSAT to SP1 version. The other option is wait for official release of Remote Server Administrator Tools for windows 7 SP1, which will happen this April.

Update 4/8/2011: Microsoft released Windows 7 SP1 RSAT Tools to public today. The download link is here http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7d2f6ad7-656b-4313-a005-4e344e43997d