Windows VMs

Installing Windows VMs on the Citrix Hypervisor server requires hardware virtualization support (Intel VT or AMD-V).

Basic procedure for creating a Windows VM

The process of installing a Windows on to a VM consists of the following steps:

  1. Selecting the appropriate Windows template

  2. Installing the Windows operating system

  3. Installing the Citrix VM Tools (I/O drivers and the Management Agent)

Warning:

Windows VMs are supported only when the VMs have the Citrix VM Tools installed. For more information, see Citrix VM Tools.

Windows VM templates

Windows operating systems are installed onto VMs by cloning an appropriate template using either XenCenter or the xe CLI, and then installing the operating system. The templates for individual guests have predefined platform flags set which define the configuration of the virtual hardware. For example, all Windows VMs are installed with the ACPI Hardware Abstraction Layer (HAL) mode enabled. If you later change one of these VMs to have multiple virtual CPUs, Windows automatically switches the HAL to multi-processor mode.

The available Windows templates are listed below:

Template Name Description
Citrix XenApp on Windows Server 2008 (32-bit) Used to install Windows Server 2008 SP2 (32-bit). All editions are supported. This template is specially tuned to optimize Citrix XenApp performance.
Citrix XenApp on Windows Server 2008 (64-bit) Used to install Windows Server 2008 SP2 (64-bit). All editions are supported. This template is specially tuned to optimize Citrix XenApp performance.
Citrix XenApp on Windows Server 2008 R2 (64-bit) Used to install Windows Server 2008 R2 and Windows Server 2008 R2 SP1 (64-bit). All editions are supported. This template is specially tuned to optimize Citrix XenApp performance.
Windows 7 (32-bit) Used to install Windows 7 and Windows 7 SP1 (32-bit).
Windows 7 (64-bit) Used to install Windows 7 and Windows 7 SP1 (64-bit).
Windows 8.1 (32-bit) Used to install Windows 8.1 (32-bit). (See note)
Windows 8.1 (64-bit) Used to install Windows 8.1 (64-bit). (See note)
Windows 10 (32-bit) Used to install Windows 10.
Windows 10 (64-bit) Used to install Windows 10 (64-bit).
Windows Server 2008 (32-bit) Used to install Windows Server 2008 SP2 (32-bit). All editions are supported.
Windows Server 2008 (64-bit) Used to install Windows Server 2008 SP2 (64-bit). All editions are supported.
Windows Server 2008 R2 (64-bit) Used to install Windows Server 2008 R2 and Windows Server 2008 R2 SP1 (64-bit). All editions are supported.
Windows Server 2012 (64-bit) Used to install Windows Server 2012 (64-bit).
Windows Server 2012 R2 (64-bit) Used to install Windows Server 2012 R2 (64-bit).
Windows Server 2016 (64-bit) Used to install Windows Server 2016 or Windows Server Core 2016 (64-bit)
Windows Server 2019 (64-bit) Used to install Windows Server 2019 or Windows Server Core 2019 (64-bit)

Note:

Windows 8 is no longer supported. Users who install Windows 8 are upgraded to Windows 8.1.

Warning:

Experimental guest operating systems have received limited testing, might not be present in future product releases, and must not be enabled on production systems. We might not respond to support requests regarding experimental features.

Attach an ISO image library

The Windows operating system can be installed either from an install CD in a physical CD-ROM drive on the Citrix Hypervisor server, or from an ISO image. See Create ISO images for information on how to make an ISO image from a Windows install CD and make it available for use.

Create a VM by using XenCenter

Note:

The following procedure provides an example of creating Windows 7 (32-bit) VM. The default values may vary depending on the operating system that you choose.

To create a Windows 7 (32-bit) VM:

  1. On the XenCenter toolbar, click the New VM button to open the New VM wizard.

    The New VM wizard allows you to configure the new VM, adjusting various parameters for CPU, storage, and networking resources.

  2. Select a VM template and click Next.

    Each template contains the setup information that is required to create a VM with a specific guest operating system (OS), and with optimum storage. This list reflects the templates that Citrix Hypervisor currently supports.

    Note:

    If the OS that you are installing on your VM is compatible only with the original hardware, check the Copy host BIOS strings to VM box. For example, you might use this option for an OS installation CD that was packaged with a specific computer.

    To copy BIOS strings using the CLI, see Install HVM VMs from Reseller Option Kit (BIOS-locked) Media. The option to set user-defined BIOS strings are not available for HVM VMs.

  3. Enter a name and an optional description for the new VM.

  4. Choose the source of the OS media to install on the new VM.

    Installing from a CD/DVD is the simplest option for getting started.

    1. Choose the default installation source option (DVD drive)
    2. Insert the disk into the DVD drive of the Citrix Hypervisor server
    3. Choose Next to proceed.

    Citrix Hypervisor also allows you to pull OS installation media from a range of sources, including a pre-existing ISO library. An ISO image is a file that contains all the information that an optical disc (CD, DVD, and so on) would contain. In this case, an ISO image would contain the same OS data as a Windows installation CD.

    To attach a pre-existing ISO library, click New ISO library and indicate the location and type of ISO library. You can then choose the specific operating system ISO media from the list.

  5. Select a home server for the VM.

    A home server is the server which provides the resources for a VM in a pool. When you nominate a home server for a VM, Citrix Hypervisor attempts to start the VM on that server. If this action is not possible, an alternate server within the same pool is selected automatically. To choose a home server, click Place the VM on this server and select a server from the list.

    Notes:

    • In WLB-enabled pools, the nominated home server isn’t used for starting, restarting, resuming, or migrating the VM. Instead, WLB nominates the best server for the VM by analyzing Citrix Hypervisor resource pool metrics and by recommending optimizations.
    • If a VM has a virtual GPU assigned to it, the home server nomination doesn’t take effect. Instead, the server nomination is based on the virtual GPU placement policy set by the user.

    If you do not want to nominate a home server, click Don’t assign this VM a home server. The VM is started on any server with the necessary resources.

    Click Next to continue.

  6. Allocate processor and memory resources for the VM. For a Windows 10 VM, the default is 1 virtual CPU and 2,048 MB of RAM. You may also choose to modify the defaults. Click Next to continue.

  7. Assign a virtual GPU. The New VM wizard prompts you to assign a dedicated GPU or a virtual GPU to the VM. This option enables the VM to use the processing power of the GPU. With this feature, you have better support for high-end 3D professional graphics applications such as CAD/CAM, GIS, and Medical Imaging applications.

  8. Allocate and configure storage for the new VM.

    Click Next to select the default allocation (24 GB) and configuration, or you might want to do the following extra configuration:

    • Change the name, description, or size of your virtual disk by clicking Properties.
    • Add a new virtual disk by selecting Add.
  9. Configure networking on the new VM.

    Click Next to select the default NIC and configurations, including an automatically created unique MAC address for each NIC. Alternatively, you might want to do the following extra configuration:

    • Change the physical network, MAC address, or Quality of Service (QoS) priority of the virtual disk by clicking Properties.
    • Add a new virtual NIC by selecting Add.
  10. Review settings, and then click Create Now to create the VM and return to the Search tab.

    An icon for your new VM appears under the host in the Resources pane.

    On the Resources pane, select the VM, and then click the Console tab to see the VM console.

  11. Follow the OS installation screens and make your selections.

  12. After the OS installation completes and the VM reboots, install the Citrix VM Tools.

Install Citrix VM Tools

Citrix Hypervisor has a simpler mechanism to install and update Citrix VM Tools (I/O drivers and the Management Agent) on Windows VMs.

Citrix VM Tools provide high performance I/O services without the overhead of traditional device emulation. Citrix VM Tools consists of I/O drivers (also known as Paravirtualized drivers or PV drivers) and the Management Agent. Citrix VM Tools must be installed on each Windows VM in order for the VM to have a fully supported configuration. A VM functions without them, but performance is significantly hampered.

Note:

To install Citrix VM Tools on a Windows VM, the VM must be running the Microsoft .NET Framework Version 4.0 or later.

To install Citrix VM Tools:

  1. Select the VM in the Resources pane, right-click, and then click Install Citrix VM Tools on the shortcut menu. Alternatively, on the VM menu, click Install Citrix VM Tools, or on the General tab of the VM, click Install I/O drivers and Management Agent.

    Note:

    When you install Citrix VM Tools on your VM, you are installing both I/O drivers (PV drivers) and the Management Agent.

  2. If AutoPlay is enabled for the VM’s CD/DVD drive, installation will start automatically after a few moments. The process installs the I/O drivers and the Management Agent. Restart the VM when prompted to get your VM to an optimized state.

  3. If AutoPlay is not enabled, click Install Citrix VM Tools to continue with the installation. This action mounts the Citrix VM Tools ISO (guest-tools.iso) on the VM’s CD/DVD drive.

    When prompted, select one of the following options to choose what happens with the Citrix VM Tools ISO:

    • Click Run Setup.exe to begin the Citrix VM Tools installation. This action opens the Citrix Hypervisor Windows Management Agent Setup wizard. Follow the instructions on the wizard to get your VM to an optimized state and perform any actions that are required to complete the installation process. When you install Citrix VM Tools using this method, the Management Agent is configured to get updates automatically. However, the management agent update mechanism does not automatically update the I/O drivers. This behavior is the default. If you prefer to change the default behavior, install Citrix VM Tools using the following method:

    • Click Open folders to view files and then run Setup.exe from the CD Drive. This option opens the Citrix Hypervisor Windows Management Agent Setup wizard and lets you customize the Citrix VM Tools installation and the Management Agent update settings.

    • Follow the instructions on the wizard to accept the license agreement and choose a destination folder.

    • Customize the settings on the Installation and Updates Settings page. The Citrix Hypervisor Windows Management Agent Setup wizard displays the default settings. By default, the wizard displays the following settings:

      • Install I/O Drivers Now

      • Allow automatic management agent updates

      • Disallow automatic I/O drivers updates by the management agent

      • Send anonymous usage information to Citrix

      If you do not want to allow the automatic updating of the Management Agent, select Disallow automatic management agent updates from the list.

      If you would like to allow the Management Agent to update the I/O drivers automatically, select Allow automatic I/O driver updates by the management agent.

      Note:

      If you have chosen to receive I/O driver updates through the Windows Update mechanism, do not allow the Management Agent to update the I/O drivers automatically.

      If you do not want to share anonymous usage information with Citrix, clear the Send anonymous usage information to Citrix check box. The information transmitted to Citrix contains the UUID of the VM requesting the update. No other information relating to the VM is collected or transmitted to Citrix.

    • Click Next and then Install to begin the Citrix VM Tools installation process.

    • When prompted, perform any actions that are required to complete the installation process.

      Note:

      The Citrix VM Tools can request to restart with /quiet /norestart or /quiet /forcerestart specified after the VM has already been restarted once as part of the installation.

    • Click Finish to exit the wizard.

    Note:

    I/O drivers are automatically installed on a Windows VM that can receive updates from Windows Update. However, we recommend that you install the Citrix VM Tools package to install the Management Agent, and to maintain supported configuration.

To install the I/O drivers and the Management Agent on many Windows VMs, install managementagentx86.msi or managementagentx64.msi using your preferred MSI installation tool. These files can be found on the Citrix VM Tools ISO.

Customers who install the Citrix VM Tools or the Management Agent through RDP may not see the restart prompt as it only appears on the Windows console session. To ensure that you restart your VM (if necessary) and to get your VM to an optimized state, specify the force restart option in RDP. The force restart option restarts the VM only if it is required to get the VM to an optimized state.

Silent installation

To install the Citrix VM Tools silently and to prevent the system from rebooting, run one of the following commands:

Msiexec.exe /package managementagentx86.msi /quiet /norestart
Msiexec.exe /package managementagentx64.msi /quiet /norestart

Or

Setup.exe /quiet /norestart

A non-interactive, but non-silent installation can be obtained by running:

Msiexec.exe managementagentx86.msi /passive
Msiexec.exe managementagentx64.msi /passive

Or

Setup.exe /passive

For interactive, silent, and passive installations, following the next system restart there might be several automated reboots before the Citrix VM Tools are fully installed. This behavior is also the case for installations with the /norestart flag specified. However, for installations where the /norestart flag is provided, the initial restart might be manually initiated.

The Citrix VM Tools are installed by default in the C:\Program Files\Citrix\XenTools directory on the VM.

Notes:

  • To install Citrix VM Tools on a Windows VM, the VM must be running the Microsoft .NET Framework Version 4.0 or later.
  • The /quiet parameter applies to the installation dialogs only, but not to the device driver installation. When the /quiet parameter is specified, the device driver installation requests permission to reboot if required.
    • When /quiet /norestart is specified, the system doesn’t reboot after the entire tools installation is complete. This behavior is independent of what the user specifies in the reboot dialog.
    • When /quiet /forcerestart is specified, the system reboots after the entire tools installation is complete. This behavior is independent of what the user specifies in the reboot dialog.
    • When the device driver installation requests permission to reboot, a tools installation with the quiet parameter specified can still be in progress. Use the Task Manager to confirm whether the installer is still running.

Warning:

Installing or upgrading the Citrix VM Tools can cause the friendly name and identifier of some network adapters to change. Any software which is configured to use a particular adapter may have to be reconfigured following Citrix VM Tools installation or upgrade.

Create a Windows VM by using the CLI

To create a Windows VM from an ISO repository by using the xe CLI:

  1. Create a VM from a template:

    xe vm-install new-name-label=vm_name template=template_name
    

    This command returns the UUID of the new VM.

  2. Create an ISO Storage Repository:

    xe-mount-iso-sr path_to_iso_sr
    
  3. List all of the available ISOs:

    xe cd-list
    
  4. Insert the specified ISO into the virtual CD drive of the specified VM:

    xe vm-cd-add vm=vm_name cd-name=iso_name device=3
    
  5. Start the VM and install the operating system:

    xe vm-start vm=vm_name
    

At this point, the VM console is visible in XenCenter.

For more information on using the CLI, see Command Line Interface.

Update Windows operating systems

This section discusses updating Windows VMs with updated operating systems and reinstalling Citrix VM Tools.

Upgrades to VMs are typically required when moving to a newer version of Citrix Hypervisor. Note the following limitations when upgrading your VMs to a newer version of Citrix Hypervisor:

  • Before migrating Windows VMs using live migration, you must upgrade the Citrix VM Tools on each VM.

  • Suspend/Resume operation is not supported on Windows VMs until the Citrix VM Tools are upgraded.

  • The use of certain antivirus and firewall applications can crash Windows VMs, unless the Citrix VM Tools are upgraded.

Warning:

Before updating Windows operating systems, uninstall the Citrix VM Tools. If they are present during the attempt to update, the update fails.

Windows installation disks typically provide an upgrade option when you boot them on a server which has an earlier version of Windows already installed.

You can update the operating system of Windows VMs in a similar way.

To uninstall the Citrix VM Tools:

  1. From the Start button, select Control Panel.

  2. Select Programs, and then select Programs and Features.

  3. Select all of the following items (the list depends on your operating system and the version of Citrix VM Tools installed on your VM):

    • Citrix Hypervisor Windows Management Agent
    • Citrix Tools for Virtual Machines
    • Citrix VM Tools Installer
    • Citrix Hypervisor Windows Guest Agent
    • Citrix Hypervisor Xen Windows x64 PV Drivers
    • Citrix Hypervisor Xen Windows x86 PV Drivers
    • Citrix Hypervisor VSS Provider
  4. Select Uninstall.

    This choice removes the Citrix VM Tools. When the operation completes, a message is displayed. Click OK to close the message box.

After the operating system update is complete, reinstall the Citrix VM Tools just as you would after installing a fresh Windows VM.

Reinstall Citrix VM Tools

The Citrix VM Tools are available in XenCenter on the built-in guest-tools.iso. On the VM menu, select Install Citrix VM Tools. This option attaches the CD image containing the Citrix VM Tools to the VM.

If AutoPlay is enabled for the VM’s CD/DVD drive, installation will start automatically after a few moments. The process installs the I/O drivers and the Management Agent. Restart the VM when prompted to get your VM to an optimized state.

If AutoPlay is not enabled, the Citrix VM Tools installer displays the installation options. Click Install Citrix VM Tools to continue with the installation. This option mounts the Citrix VM Tools ISO (guest-tools.iso) on the VM’s CD/DVD drive. Click Run setup.exe to begin Citrix VM Tools installation and restart the VM when prompted to get your VM to an optimized state.

Update Citrix VM Tools

Citrix Hypervisor has a simpler mechanism to update I/O drivers (PV drivers) and the Management Agent automatically for Windows VMs. This mechanism enables customers to install updates as they become available, without having to wait for a hotfix.

The Virtualization state section on a VM’s General tab in XenCenter specifies whether the VM can receive updates from Windows Update. The mechanism to receive I/O driver updates from Windows Update is turned on by default. If you do not want to receive I/O driver updates from Windows Update, disable Windows Update on your VM, or specify a group policy.

The following sections contain information about automatically updating the I/O drivers and the Management Agent.

Update the I/O drivers

You can get I/O driver updates automatically from Microsoft Windows Update, provided:

  • You are running Citrix Hypervisor 8.0 Premium Edition, or have access to Citrix Hypervisor through Citrix Virtual Apps and Desktops entitlement.

  • You have created a Windows VM using XenCenter issued with Citrix Hypervisor 8.0

    Important:

    VMs imported from earlier versions of Citrix Hypervisor are not capable of receiving I/O drivers from Windows Update.

  • Windows Update is enabled within the VM

  • The VM has access to the internet, or it can connect to a WSUS proxy server

Note:

Windows Server Core does not support using Windows Update to install or update the I/O drivers. Instead use the installer on the Citrix VM Tools ISO.

Note:

Customers can also receive I/O driver updates automatically through the automatic Management Agent update mechanism. You can configure this setting during Citrix VM Tools installation. For more information, see Installing Citrix VM Tools.

Find the I/O driver version

To find out the version of the I/O drivers installed on the VM:

  1. Navigate to C:\Windows\System32\drivers.

  2. Locate the driver from the list.

  3. Right-click the driver and select Properties and then Details.

    The File version field displays the version of the driver installed on the VM.

Update the Management Agent

Citrix Hypervisor enables you to update the Management Agent automatically on both new and existing Windows VMs. By default, Citrix Hypervisor allows the automatic updating of the Management Agent. However, it does not allow the Management Agent to update the I/O drivers automatically. You can customize the Management Agent update settings during Citrix VM Tools installation. The automatic updating of the Management Agent occurs seamlessly, and does not reboot your VM. In scenarios where a VM reboot is required, a message appears on the Console tab of the VM notifying users about the required action.

You can get the Management Agent updates automatically, provided:

  • You are running Citrix Hypervisor 8.0 Premium Edition, or have access to Citrix Hypervisor through Citrix Virtual Apps and Desktops entitlement.

  • You have installed Citrix VM Tools issued with Citrix Hypervisor 7.0 or higher

  • The Windows VM has access to the Internet

Important:

Updates to Citrix VM Tools can also be issued through the standard Citrix Hypervisor update (hotfix) mechanism. Such hotfixes contain updates to both I/O drivers and the Management Agent. There is no licensing restriction to update Citrix VM Tools issued as a hotfix.

Find the Management Agent version

To find out the version of the Management Agent installed on the VM:

  1. Navigate to C:\Program Files\Citrix\XenTools.

  2. Right-click XenGuestAgent from the list and click Properties and then Details.

    The File version field displays the version of the Management Agent installed on the VM.

Manage Automatic Updates by using the CLI

Citrix Hypervisor enables you to use command line to manage the automatic updating of the I/O drivers and the Management Agent. You can run setup.exe or msiexec.exe with the arguments listed in the following table to specify whether the I/O drivers and the Management Agent are automatically updated. For information about installing Citrix VM Tools using setup.exe or msiexec.exe, see Silent installation.

Note:

For VMs managed using either PVS or MCS, automated updates are turned off automatically when the Citrix Virtual Desktops VDA is present and it reports that the machine as non-persistent.

Argument Values Description
ALLOWAUTOUPDATE YES/NO Allow/disallow auto updating of the Management Agent
ALLOWDRIVERINSTALL YES/NO Allow/disallow the Citrix VM Tools installer to install I/O drivers
ALLOWDRIVERUPDATE YES/NO Allow/disallow the Management Agent to update the I/O drivers automatically
IDENTIFYAUTOUPDATE YES/NO Allow/disallow the auto update mechanism to send anonymous usage information to Citrix

For example:

setup.exe  /passive /forcerestart ALLOWAUTOUPDATE=YES ALLOWDRIVERINSTALL=NO \
     ALLOWDRIVERUPDATE=NO IDENTIFYAUTOUPDATE=YES

Or

msiexec.exe /i managementagentx64.msi ALLOWAUTOUPDATE=YES ALLOWDRIVERINSTALL=NO \
    ALLOWDRIVERUPDATE=NO IDENTIFYAUTOUPDATE=YES

Redirect the Management Agent updates

Citrix Hypervisor enables customers to redirect Management Agent updates to an internal web server before they are installed. This redirection allows customers to review the updates before they are automatically installed on the VM.

To redirect the Management Agent updates:

  1. Download the TSV file from https://pvupdates.vmd.citrix.com/updates.latest.tsv.

  2. Download the Management Agent MSI files referenced in the TSV file.

  3. Upload the MSI files to an internal web server that your VMs can access.

  4. Update the TSV file to point to the MSI files on the internal web server.

  5. Upload the TSV file to the web server.

Automatic updates can also be redirected on a per-VM or a per-pool basis. To redirect updates on a per-VM basis:

  1. On the VM, open a command prompt as an administrator.

  2. Run the command

    reg.exe ADD HKLM\SOFTWARE\Citrix\XenTools /t REG_SZ /v update_url /d \
        url of the .tsv file on the web server
    

To redirect automatic updating of the Management Agent on a per-pool basis, run the following command:

xe pool-param-set uuid=pooluuid guest-agent-config:auto_update_url=url of the .tsv file on the web server

Disable the Management Agent updates

To disable automatic updating of the Management Agent on a per-VM basis:

  1. On the VM, open a command prompt as an administrator.

  2. Run the following command:

    reg.exe ADD HKLM\SOFTWARE\Citrix\XenTools /t REG_DWORD /v DisableAutoUpdate /d 1
    

To disable automatic updating of the Management Agent on a per-pool basis, run the following command:

xe pool-param-set uuid=pooluuid guest-agent-config:auto_update_enabled=false

Modify the automatic I/O driver update settings

During Citrix VM Tools installation, you can specify whether you would like to allow the Management Agent to update the I/O drivers automatically. If you prefer to update this setting after completing the Citrix VM Tools installation process, perform the following steps:

  1. On the VM, open a command prompt as an administrator.

  2. Run the following command:

    reg.exe ADD HKLM\SOFTWARE\Citrix\XenTools\AutoUpdate /t REG_SZ /v \
        InstallDrivers /d YES/NO
    

To send anonymous usage information to Citrix:

During Citrix VM Tools installation, you can specify whether you would like to send anonymous usage information to Citrix. If you would like to update this setting after completing the Citrix VM Tools installation process, perform the following steps:

  1. On the VM, open a command prompt as an administrator.

  2. Run the following command:

    reg.exe ADD HKLM\SOFTWARE\Citrix\XenTools\AutoUpdate REG_SZ /v \
        IDENTIFYAUTOUPDATE /d YES/NO
    

Prepare to clone a Windows VM by using Sysprep

The only supported way to clone a Windows VM is by using the Windows utility sysprep to prepare the VM.

The sysprep utility changes the local computer SID to make it unique to each computer. The sysprep binaries are located in the C:\Windows\System32\Sysprep folder.

Note:

For older versions of Windows, the sysprep binaries are on the Windows product CDs in the \support\tools\deploy.cab file. These binaries must be copied to your Windows VM before using.

To clone Windows VMs:

  1. Create, install, and configure the Windows VM as desired.

  2. Apply all relevant Service Packs and updates.

  3. Install the Citrix VM Tools.

  4. Install any applications and perform any other configuration.

  5. Run sysprep. This utility shuts down the VM when it completes.

  6. Using XenCenter convert the VM into a template.

  7. Clone the newly created template into new VMs as required.

  8. When the cloned VM starts, it completes the following actions before being available for use:

    • It gets a new SID and name
    • It runs a mini-setup to prompt for configuration values as necessary
    • Finally, it restarts

    Note:

    Do not restart the original, sys-prepped VM (the “source” VM) again after the sysprep stage. Immediately convert it to a template afterwards to prevent restarts. If the source VM is restarted, sysprep must be run on it again before it can be safely used to make more clones.

For more information about using sysprep, visit the following Microsoft website:

Windows VM release notes

There are many versions and variations of Windows with different levels of support for the features provided by Citrix Hypervisor. This section lists notes and errata for the known differences.

General Windows issues

  • When installing Windows VMs, start off with no more than three virtual disks. After the VM and Citrix VM Tools have been installed, you can add extra virtual disks. Ensure that the boot device is always one of the initial disks so that the VM can successfully boot without the Citrix VM Tools.

  • When the boot mode for a Windows VM is BIOS boot, Windows formats the primary disk with a Master Boot Record (MBR). MBR limits the maximum addressable storage space of a disk to 2 TiB. To use a disk that is larger than 2 TiB with a Windows VM, do one of the following things:

    • If UEFI boot is supported for the version of Windows, ensure that you use UEFI as the boot mode for the Windows VM.
    • Create the large disk as the secondary disk for the VM and select GUID Partition Table (GPT) format.
  • Multiple vCPUs are exposed as CPU sockets to Windows guests, and are subject to the licensing limitations present in the VM. The number of CPUs present in the guest can be confirmed by checking Device Manager. The number of CPUs actually being used by Windows can be seen in the Task Manager.

  • The disk enumeration order in a Windows guest may differ from the order in which they were initially added. This behavior is because of interaction between the I/O drivers and the Plug-and-Play subsystem in Windows. For example, the first disk may show up as Disk 1, the next disk hot plugged as Disk 0, a subsequent disk as Disk 2, and then upwards in the expected fashion.

  • A bug in the VLC player DirectX back-end replaces yellow with blue in video playback when the Windows display properties are set to 24-bit color. VLC using OpenGL as a back-end works correctly, and any other DirectX-based or OpenGL-based video player works too. It is not a problem if the guest is set to use 16-bit color rather than 24.

  • The PV Ethernet Adapter reports a speed of 1 Gbps in Windows VMs. This speed is a hardcoded value and is not relevant in a virtual environment because the virtual NIC is connected to a virtual switch. The data rate is not limited by the advertised network speed.

Windows 7

Microsoft only supports the use of Windows 7 when Service Pack 1 is installed. For a Windows 7 VM to be supported on Citrix Hypervisor, ensure that SP1 or later is installed.

Windows 8

We no longer support Windows 8 guests. If you install a Windows 8 VM, it is upgraded to Windows 8.1.

Windows Server 2008 R2

Microsoft only supports the use of Windows Server 2008 R2 when Service Pack 1 is installed. For a Windows Server 2008 R2 VM to be supported on Citrix Hypervisor, ensure that SP1 or later is installed.