Two new products in the world of desktop virtualization have hit the market recently; Citrix XenDesktop 5.5 and VMware vSphere 5.  With these two products coming out so close together it begs a question:  How do they integrate?  While I’m sure there will be much written on features, functions and scalability in the coming months, Citrix has certified XenDesktop 5.5 on vSphere 5 (see John Fanelli’s blog post here or visit Citrix at VMworld booth #541 for details). 

Citrix Worldwide Consulting Solutions has created a first-look architecture overview of XenDesktop on vSphere 5.  The focus of this paper is on the core functionality of XenDesktop 5.5, and looks at the Citrix FlexCast hosted VDI models.  The focus is on three technologies within the model, as detailed below.

  • Existing Desktops:  Existing desktops are single virtual desktop instances where each desktop is its own complete desktop environment with a unique copy of the desktop operating system.  End users have full control to modify the desktop once installation has completed. 
  • Machine Creation Services (MCS):  MCS provides a mechanism to thin-provision a virtual desktop from a master image in the hypervisor pool and utilize identity management functionality to overcome the security identity (SID) requirements typical with cloning.  Machine Creation Services is managed by the XenDesktop Desktop Delivery Controllers and utilize the capabilities of the underlying hypervisor to clone and thin-provision the master image. 
  • Provisioning Services: Virtual Desktops delivered through Provisioning Services rely on network booting and streaming to deliver portions of the desktop image on an as-needed basis.  Provisioning Services utilizes identity management functionality similar to Machine Creation Services.  Additional server resources are required for Provisioning Services, which may be physical or virtual.  Provisioning Services can stream to both virtual and physical desktops. 

The whitepaper covers a high-level architecture view for XenDesktop and vSphere and some setup considerations that are unique to the configuration.   For example, when installing VMware tools and the Citrix Virtual Desktop Agent (VDA), organizations need to make sure that the VDA is installed last as both agents install a WDDM video driver, and XenDesktop 5.5 requires the Citrix WDDM driver to operate correctly.  Detailed testing and scalability analysis was not part of this paper.  Configuration of core XenDesktop functionality worked without issues across a vSphere cluster configuration. 

You can find the full whitepaper here –

Let me know what you think. 


Rich Meesters