Create a Platform Layer (Citrix MCS for Nutanix AHV)

In this article:

For cross-platform deployments, a Platform Layer includes the platform software and settings required to deploy images in your environment.

You can create two kinds of Platform Layers:

• Platform Layers for publishing Layered Images (Required) - These Layers include the software and settings required for a Layered Image to run flawlessly in your environment. Use this type of Platform Layer when publishing Layered Images to a platform other than the one where you created the OS Layer.

• Platform Layers for packaging Layers (Required in some cases) - These Layers include the hypervisor software and settings you need to easily install the software for your other layers on a VM in your hypervisor environment. Use this type of Platform Layer when creating Layers on a platform other than the one from which you imported the OS for your OS Layer.

Prerequisites

Citrix MCS prerequisites

When creating a Platform Layer for publishing images to an MCS environment, you need:

• An OS Layer

• Network access to Unidesk Tools

  Access from the Platform Layer Packaging Machine VM to the Unidesk Tools download (available on the Unidesk Download page).

• Citrix Virtual Delivery Agent (VDA) installed on the Platform Layer

  The Citrix VDA installer for the Windows OS you are using must be installed on the Platform Layer.

• Citrix Desktop Delivery Controller (DDC)

  The Citrix DDC software must be installed on the server where the Layered Image will be published.

  As part of the Connector Configuration, if you include a script to run on the newly published Layered Image, you will need the following:

  • Unidesk Agent - Installed and running on the DDC. This allows Unidesk to run the script on the DDC.
  • PowerShell Snap-in - Appropriate PowerShell Snap-in must be installed on the DDC.

• Citrix resource information

  The Citrix info listed in this MCS Connector Configuration topic.

Nutanix AHV (Acropolis) prerequisites

• Nutanix Prism account and privileges

  • A Nutanix Prism account (new or existing) to use for Unidesk.
  • The account must have privileges to perform the following operations:

    • VM operations:

      • clone

      • delete

      • power on/off

      • attach virtual disks

    • Image operations:

      • create

      • update (aka upload)

      • delete

    • Virtual disks
      • create
      • attach to VMs

• Nutanix AHV software and settings

  Access to the VM Mobility Tools to install on the layer.

• Nutanix AHV resource information

  The Acropolis Server info listed in Nutanix AHV Connector Configuration or MCS for Nutanix AHV Connector Configuration.

• Nutanix AHV Connector

  When creating Layers for the Nutanix environment, you must use a Nutanix AHV Connector Configuration. The MCS for Nutanix AHV Connector does not support Layer creation.

Prepare a new Platform Layer

1. Select Layers > Platform Layers and select Create Platform Layer in the Action bar. This opens the Create Platform Layer wizard.

2. In the Layer Details tab, enter a Layer Name and Version, both required values. Optionally, you can also enter other values.

3. In the OS Layer tab, select the OS Layer you want to associate with this Platform Layer.

4. In the Connector tab, choose a Connector Configuration for the platform where you are creating this layer. If the configuration you need isn't listed, Click New, select an MCS for Nutanix AHV Connector from this list, and Add a Configuration for it.

   Important: The MCS for Nutanix AHV Connector can only be used to publish Layered Images, not to create Layers.

5. In the Platform Types tab, select the radio button that describes the purpose of this Platform Layer: to create and update layers, or to publish Layered Images. For more about these choices, see Platform Layers.

6. From the drop-down menus, select the hypervisor, provisioning service, and connection broker you are using, in this case, Nutanix AHV and Citrix MCS.

7. In the Packaging Disk tab, enter a file name for the Packaging Disk, and select the disk format. This disk will be used for the Packaging Machine (the VM) where you will install the tools, as described in the next two sections.

8. In the Icon Assignment tab, select an icon to assign to the layer. This icon represents the layer in the Layers Module.

   • To use an existing image, select an image in the image box.
   • To import a new image, click Browse and select an image in PNG or JPG format.

9. In the Confirm and Complete tab, review the details of the App Layer, enter a comment if required, and click Create Layer. Any comments you enter will appear in the Information view Audit History.

10. Expand the Tasks bar at the bottom of the UI, and double-click the Packaging Disk task to show the full task description.

    Once the Packaging Disk has been created, the Task bar displays the location of the Packaging Disk in your environment (example task message shown below).

    

Next, you can access the Packaging Machine for your Layer, and install the software for your environment.

The Packaging Machine is a virtual machine where you install the tools for your selected environment(s). It is a temporary VM that will be deleted once the new Platform Layer has been finalized. When the Unidesk software powers on the Packaging Machine for you.

Access the Packaging Machine in Nutanix AHV

1. Log into Nutanix Prism.

2. Back in the Unidesk Management Console (UMC), expand the Tasks bar at the bottom of the UI, and double-click the Create Platform Layer task to see the full Task Description (example below).

   

3. Use the instructions in the Task Description to navigate to the Packaging Machine in Prism.

Install the required platform tools

If you created the OS Layer on a hypervisor other than Nutanix, install the VM Mobility Tools. (If the OS was created in Nutanix, it already has the tools installed.) The tools installation may require multiple reboots. Once complete, you should see that you have access to the tools, as well as all of the data available under the Performance tab for your VM.

When installing your platform software on the Packaging Machine, keep in mind that the state of the software before you finalize the layer is what the image will use.

To install the tools for the selected platform:

1. Remote log in to the Packaging Machine you created. Be sure to log in using the User account you used to create the OS.

2. Install the platform software and tools, along with any drivers, boot-level applications, or files needed.

   • If this Platform Layer is going to be used for publishing Layered Images, install and configure your hypervisor, provisioning service, and connection broker tools and settings.
   • If a software installation requires a system restart, restart it manually. The Packaging Machine does not restart automatically.

3. Install an empty flag file called Shutdown_published_Image.txt in the following directory:

     c:\windows\setup\scripts\kmsdir

   This enables automated shutdown of the OS.

4. Make sure the Packaging Machine is in the state you want it to be in when the image is booted:

   • If the tools you install require any post-installation setup or registration, complete those steps now.
   • Remove any settings, configurations, files, mapped drives, or applications that you do not want to include on the Packaging Machine.

Next, you'll need to shut down the Packaging Machine and verify that the Platform Layer is ready to finalize.

Verify the Layer and shut down the Packaging Machine

Once the tools are installed on the Packaging Machine, the next step is to verify that the Layer is ready to finalize. At this point, any required post-installation processing needs to be completed. For example, a reboot may be required, or a Microsoft NGen process may need to complete.

To verify that any outstanding processes are complete, you can run the Shutdown For Finalize tool (icon below), which appears on the Packaging Machine's desktop.

To use the Shutdown For Finalize tool:

1. If you are not logged into the Packaging Machine, remote log in as the user who created the machine.

2. Double-click the Shutdown For Finalize icon. A command line window displays messages detailing the layer verification process.

3. If there is an outstanding operation that must be completed before the Layer can be finalized, you are prompted to complete the process. For example, if a Microsoft NGen operation needs to complete, you may be able to expedite the NGen operation, as detailed below.

4. Once any pending operations are complete, double-click the Shutdown For Finalize icon again. This shuts down the Packaging Machine.

The Shutdown for Finalize task will remain in the Action Required state until you finalize the Layer.

The Layer is now ready to finalize.

Layer integrity messages you may see during the finalization process

Layer integrity messages let you know what queued tasks must be completed before a Layer is finalized.

The new Layer or Version can only be finalized when the following conditions have been addressed:

• A reboot is pending to update drivers on the boot disk - please check and reboot the Packaging Machine.
• A post-installation reboot is pending - please check and reboot the Packaging Machine.
• An MSI install operation is in progress - please check the Packaging Machine.

• A Microsoft NGen operation is in progress in the background.

  Note: If a Microsoft NGen operation is in progress, you may be able to expedite it, as described in the next section.

Expediting a Microsoft NGen operation

NGen is the Microsoft Native Image Generator. It is part of the .NET system, and basically re-compiles .NET byte code into native images and constructs the registry entries to manage them. Windows will decide when to run NGen, based on what is being installed and what Windows detects in the configuration. When NGen is running, you must let it complete. An interrupted NGen operation can leave you with non-functioning .NET assemblies or other problems in the .NET system.

You have the choice of waiting for the NGen to complete in the background, or you can force the NGen to the foreground. You can also check the status of the NGen operation, as described below. However, every time you check the queue status, you are creating foreground activity, which might cause the background processing to temporarily pause.

Forcing the NGen to the foreground will allow you to view the progress and once the output has completed, you should be able to finalize the layer.

1. Force an NGen operation to the foreground.

   Normally, NGen is a background operation and will pause if there is foreground activity. Bringing the task into the foreground can help the task to complete as quickly as possible. To do this:

   1. Open a command prompt as Administrator.

   2. Go to the Microsoft .NET Framework directory for the version currently in use:

      cd C:\Windows\Microsoft.NET\FrameworkNN\vX.X.XXXXX

   3. Enter the NGen command to execute the queued items:

      ngen update /force

      This brings the NGen task to the foreground in the command prompt, and lists the assemblies being compiled.

      Note: It’s okay if you see several compilation failed messages!

   4. Look in the Task Manager to see if an instance of MSCORSVW.EXE is running. If it is, you must allow it to complete, or re-run ngen update /force. Do not reboot to stop the task. You must allow it to complete.

2. Check the status of an NGen operation

   1. Open a command prompt as Administrator.

   2. Check status by running this command:

      ngen queue status

   3. When you receive the following status, the NGen is complete, and you can finalize the Layer.

      The .NET Runtime Optimization Service is stopped

Finalize the Layer

Once the Packaging Machine is created, the tools are installed and ready to finalize, and you have shut down the machine, you'll need to finalize the layer.

When a layer is ready to finalize:

1. Return to the Unidesk Management Console.
2. Select Layers > Platform Layers, and select the Platform Layer you just prepared.
3. Select Finalize in the Action bar.
4. Monitor the Task bar to verify that the action completes successfully and that the layer is deployable.