Tired of the quaint Windows 7 Basic Theme of your VDI desktop? Looking to deliver a modern experience on your capable Windows XP devices with zero effort? Check out the new Aero Redirection feature in XenDesktop 5.5.

HDX RichGraphics Aero Redirection delivers the full Windows 7 Aero Glass experience for VDI desktops. It provides an immersive look-and-feel like the local Windows 7 Aero Glass desktop even on client computers running Windows XP. (It also supports Windows Thin PC, Windows Embedded Standard, Windows 7 and Vista.)

The benefits are numerous and cumulatively amount to an inspiring and productive experience.

Lightweight translucent windows with glassy borders and panes, glowing buttons, drop shadows, smooth dragging, subtle window animations, Thumbnail Previews, Aero Shake, Snap, Peek, Flip 3d, to name a few.

The Aero mouse scheme with animated color cursors and drop shadows rendered locally on the client adds to a snappy, enjoyable Aero Glass experience delivered from VDI.

Aero Redirection leverages the client video card (GPU) or Integrated Graphics Processor (IGP) and requires no video card in the data center. Graphics rasterization is performed by the client GPU; the processor (CPU) on both ends is only used for protocol compression to reduce the amount of bandwidth required to carry the graphics commands. Rasterizing Aero on the client GPU instead of in the data center increases VDI scalability and user density and lowers the costs inherent in delivering the Aero Glass experience. No expensive, bulky, power-hungry GPU boards are required in the data center. Instead, the client GPU that came with the device is used.

Aero Redirection provides the ultimate form of GPU virtualization (vGPU) since it is agnostic to the type, capabilities, or vendor of the client GPU and provides vGPU plug-and-play (PnP) from one connection to the next without reboot or even logoff.

Got a second client monitor? Not a problem. Aero Redirection supports multi-monitor PnP just as well. Just maximize your Aero Redirection session across both monitors and those will automatically plug in on-the-fly inside the session. There is no need to decide in advance how many monitors your Aero Redirection session will have or the display resolution since the client device you use can change from one connection to the next.

Similarly, if you connect from a client device or from a network connection that does not meet the Aero Redirection requirements the Windows Basic Theme will be delivered by the veteran HDX “Thinwire” display driver. Aero Redirection monitors the user experience and if it detects insufficient connection bandwidth or client computing resources, it automatically switches to resource-friendly GDI graphics and Thinwire.

Aero Redirection requirements

This first release of Aero Redirection is designed for “rich clients” (essentially, PCs). Client computers must meet the following software, hardware, and video card minimum requirements to be able to receive Aero graphics:

  • 2 gigahertz (GHz) 32-bit (x86) or 64-bit (x64) processor non-mobile (3 GHz recommended)
  • 1.5 gigabyte (GB) of random access memory (RAM)
  • DirectX 9 class graphics card that supports Pixel Shader 2.0 in hardware with 128-megabyte (MB) video memory
  • DirectX 9 runtime (Windows XP, Vista, Windows 7). ThinPC and XPe are supported if the DirectX 9 runtime binaries have been preinstalled.
  • Connection bandwidth of 3 Mbps available per user (Broadband 6 Mbps recommended)
  • Citrix Receiver 3.0 for Windows

Aero Redirection is only available with XenDesktop 5.5 on Windows 7 VDAs through VDI deployment. It is supported on the following hypervisors:

  • Citrix XenServer 5.6 and above
  • VMware ESX
  • Microsoft Hyper-V

VDAs must be configured with minimum 1.5 GB of RAM without overcommit.

Troubleshooting, tips and tricks

Aero Redirection is automatically installed with XenDesktop 5.5 on Windows 7 VDAs on XenServer 5.6 and above and ESX hypervisors. To install Aero Redirection on Hyper-V without RemoteFX, specify the command-line option /CITRIXWDDMONHYPERV to the metainstaller (XenDesktopVdaSetup.exe /CITRIXWDDMONHYPERV). If RemoteFX is installed the command-line has no effect. Aero Redirection cannot be installed on any other VDAs, including physical.

Aero Redirection first must be enabled by HDX user policy under Desktop UI. Thereafter, users can choose to enable and disable Aero by switching the Windows Theme in the Themes applet in the VDA.

The first release of Aero Redirection is optimized for one or two monitors. When more than two monitors are used, the Aero Basic Theme should be used for optimal performance.

To prevent Aero Redirection from switching to the Windows Basic Theme due to insufficient connection or client computing resources, the admin can add the following setting in the windows registry in the VDA:

HKLM\Software\Citrix\Vd3d\MinFps REG_DWORD  0.

The setting can be also added by the user in the user profile under HKCU\Software\Citrix\Vd3d. On 64-bit VDAs, use the Software\Wow6432Node\Citrix\Vd3d location for both HKLM and HKCU.

If the minimum software and hardware requirements are not met at connection establishment time, the Windows 7 Basic Theme is delivered by Thinwire instead.

For specific Aero Redirection troubleshooting and diagnostic messages, check out the Windows event log in the VDA under Applications and Services\Citrix\Graphics\Vd3d.