A new known feature in Windows Server 2008 R2 that could be described as RemoteApp for Hyper-V. Like Microsoft RemoteApp, it allows users to access a specific hosted application remotely, as opposed to the entire desktop. With RemoteApp, the application runs in the context of a server session; however, RemoteApp for Hyper-V enables remote access to an application running in a Hyper-V VM.

With the advent of Windows 7, some enterprise customers were facing application compatibility issues with line-of-business applications that were specifically written for Windows XP and would not work on Windows 7.

One obvious way to resolve this issue is to run those incompatible applications in Windows XP Mode, a new feature that is available in certain Windows 7 SKUs and which simplifies migration to the new OS by allowing legacy XP applications to seamlessly run in their own context within a Windows 7 environment. Windows XP mode has specific hardware, OS and memory requirements. While this solution works well on newer machines with hardware virtualization support, the hardware requirements for XP mode might be prohibitive for some older PCs.

RemoteApp for Hyper-V allows users to remotely access Windows XP applications from their Windows 7 desktop with no additional hardware requirements.

• SKU support: RemoteApp for Hyper-V is supported on the following SKUs running as the guest OS:
  • Windows XP SP3: Professional
  • Windows Vista SP1 and above: Enterprise and Ultimate
  • Windows 7: Enterprise and Ultimate

Here are some examples of applications that will benefit from this feature:

• • Applications that are compatible only with Windows XP SP3
  • Applications that can run on Windows Server 2003, but not Windows Server 2008 or Windows Server 2008 R2
  • Applications that are supposed to be run only on a data center server for data security or compliance reasons

To use this feature, a user connects remotely from a client computer to the VM-hosted application. To host the applications, an administrator sets up a virtual machine with a guest OS on a Hyper-V server hosting the virtual machine.

The client computer must run Windows 7, but the guest OS on the virtual machine can run Windows XP SP3, Windows Vista (with SP1 and above) or Windows 7. For a guest OS running Windows XP SP3, an update is required; for a guest OS running Windows Vista SP1 or above, another update is needed.

• So, how can an administrator deploy this?

There are two ways in which RemoteApp for Hyper-V can be deployed. The first way is the stand-alone scenario, in which all the administrator needs to do is set up a Hyper-V server with virtual machines running a client OS (for example, Windows XP SP3). The administrator would then set up the application and create RDP files that launch this application. A user can connect to the application via a simple Remote Desktop connection using the RDP file.

Here’s how this setup would look:

While this is a simple setup that an administrator can use to pilot the RemoteApp for Hyper-V, it offers no extra efficiency or ability to load balance. One serious drawback of this method is that since only one user can connect to an application at a time, one user connecting to multiple virtual machines effectively blocks out other users.

To get around this problem, the recommended way to install RemoteApp for Hyper-V is over a complete VDI farm or personal virtual desktop setup, including setting up the RD Connection Broker role. An administrator would still need to perform the same manual steps of setting up the application and creating an RDP file, but there are significant advantages to going through the RD Connection Broker. An obvious one is load balancing. In addition, there is increased efficiency, simply because when a user is connected to a virtual machine, all applications launched by that user are redirected to the same virtual machine. Only one user can connect to applications running on a particular virtual machine at a time.

One single user cannot block out an entire farm by holding onto different virtual machines on it at the same time. Until a user’s virtual machine is terminated, redirection is always to the same VM. RD Connection Broker ensures that a user connected to a VM stays connected until logged out.

Here’s how the second setup scenario described above would look (running from a Windows XP SP3 farm, for instance):

Hosting applications in a farm of virtual machines running Windows XP SP3 is a simple way to give multiple people on the domain access to the applications. There is no security filtering for applications on a virtual machine farm. All domain users who have access to the farm will have access to the applications.

If an administrator wants to give only a specific user access to an application, the application should be hosted on a personal desktop. In all cases--farms or personal desktops--an administrator only needs to create an RDP file and hand it over to a user, either via a network share or email.

RemoteApp for Hyper-V is a basic but powerful platform capability which was designed with advanced administrators in mind who are willing to do the manual configuration steps to enable an environment that includes remote access to VM-hosted applications. It serves also as an extensibility point for our RDS partner ecosystem who may want to take advantage of this infrastructure capability and provide additional value-add to RDS customers by streamlining the configuration and expanding the usability and manageability of it. For example, with additional code, it is possible to integrate the RDP files with Remote Desktop Web Access.

Related links:

Update package for Windows XP SP3:

http://www.microsoft.com/downloads/details.aspx?FamilyID=2f376f53-83cf-4e5b-9515-2cb70662a81b&displaylang=en

Update package for Windows Vista SP1 or above:

http://www.microsoft.com/downloads/details.aspx?familyid=097B7478-3150-4D0D-A85A-6451F32C459C&displaylang=en