Introduction

The following article takes you through the steps required to implement SCCM within a XenDesktop VDI environment. From the creation of the master image client installation to the addition of the virtual device classes.

Allow the Master Image workstation to have the SCCM client installed

Under a VDI solution only the master VM image needs to have the SCCM client installed. When the master image is created with MCS install the SCCM agent on that master VM. VDI's that are created from the master image will generate their own machine ID's that will persist with the device.This means that the devices will appear in the console alongside the physical devices, one record per device.

Run AD Users and Computers. Create an account that will be used to push install the SCCM client to the master image. In this instance an account called SCCMLocalAdmin has been created. Set the password to never expire.

Add the account to the local administrator group on the master image machine.

Set the account as the Client Push Account

In the Administration workspace; click Site Configuration>Sites. Right click the site in the main body pane and choose Client Installation Settings>Client Push Installation. Click the Accounts tab and then the yellow star burst icon and choose New Account.

Add in the username/password for the SCCMLocalAdmin account. Click OK twice.

Install the SCCM Client

With the above criteria in place SCCM 2012 will install the SCCM Client onto the VDI master VM. Ensure that the following are allowed through the Windows Firewall if using the Push install method.

• WMI
• File and Print Sharing

Once install completes you will need to make the following changes to the master image prior to snapshot.

1. Stop the SMS Host Service – to do this run the command net stop ccmexec as an administrator
2. Delete the SMSCFG.ini file from the Windows folder – to do this run the command del %WINDIR%\smscfg.ini
3. Delete the SMS certificates – to do this run the following line in PowerShell – Remove-Item -Path HKLM:\Software\Microsoft\SystemCertificates\SMS\Certificates\* -Force or from DOS using powershell -command "Remove-Item -Path HKLM:\Software\Microsoft\SystemCertificates\SMS\Certificates\* -Force"
4. Remove the Inventory Action ID 1 in WMI – to do this run the command 

Do not follow the advice from the Citrix Team Blog which is to install the client and forget about it. This approach will generate bad mifs in your environment. See my post on the subject here.

Defining the SCCM Client Settings within a VDI environment

Since the master image is the reference point for all your updates you only want to update that master image during any patching exercises. If you applied any updates to the cloned desktops these would be lost on a log off and therefore generate unnecessary network traffic and disk activity when downloaded and installed again. SCCM 2012 provides a way to disable the update deployment. According to The Citrix Blog

'To address this, Configuration Manager 2012 provides a simple mechanism to disable the update deployment. In the Configuration Manager console you can define a custom client setting for the Computer Agent. Within that there is an option called ‘Agent extensions manage the deployment of applications and software updates.’ – pre SP1 and ‘Additional software manages the deployment of applications and software updates’ – post SP1 Setting that to Yes instructs the SCCM agent to do all of its normal information discovery operations but not attempt to download/apply any software updates. Once you have defined this policy you can apply it to any collections of virtual desktops which are built on shared images. Your master VMs can be in different collections which don’t have this policy applied so that they will continue to download and apply updates.'

I would advise against applying this to your clients. The main reason being that if you are using application deployment such as App-V your packages will fail to deploy if you enable this in your client settings (note MSI deployment still works). Hmm not good!

Also if you decide to deploy updates that are targeted to the cloned devices, and not the master, they will still download - but not install - to the device.

Just take care when targeting the deployment of updates!

If you decide to go ahead, enable this client setting as below.  Target the client policy at the cloned VDI's only (details on how to create your collection later).

Click Computer Agent and change the value for ‘Additional software manages the deployment of applications and software updates’ to Yes. Click OK.

Create a Master Image collection

Create a collection for the master image. This can assist with targeting software update deployments Add in the device using either a direct or query rule. I tend to add in direct for this single device collection.

To create a direct rule collection that will contain only the master image VM, go to the Assets and Compliance workspace, right click the Device Collection node and choose Create Device Collection.

Add a Name for the collection and click the Browse button to choose a Limiting Collection. Choose All Systems as the limiting collection. Click Next.

Click Add Rule>Direct Rule. Add in the master image VM.  Click through to the end of the wizard.

Refresh the Device Collections and the Member Count will increment by the number of workstations added.

If you have set the client previously at the Default Client Policy level then be sure to set the master image to use SCCM to handle updates with a separate policy. Again, my advice, don't use the Citrix recommended method.

Configuring Software Updates

In the Assets and Compliance workspace right click Device Collections and choose Folder>Create Folder. Name it 'Software Updates'.

Create a sub folder called Software Updates – Windows 7. Right click the Software Updates – Windows folder and create a Device Collection.

Enter a name for the Collection. In this instance the software updates will be targeted at the master image VM only, I name this collection ‘Software Updates - Master Image’. Click Browse and use the All Master Image Devices collection created earlier.

Add in the master image VM by either a direct or query rule and click through to the end of the wizard.

When creating my ADR for updates I ensure that the collection that is targeted for deploy is the 'Software Updates - Master Image' collection.

When I schedule the ADR to run I then ensure that the master image is powered on and available. Once updates are deployed to the master image I can then snapshot the master VM and update the Citrix catalogs with the changes.