About Virtual Desktop Infrastructure
Updated: February 16, 2011
Applies To: Windows Server 2008 R2
What is Virtual Desktop Infrastructure?
Remote Desktop Virtualization Host (RD Virtualization Host) is a new Remote Desktop Services role service included with Windows Server 2008 R2. RD Virtualization Host integrates with the Hyper-V role to provide virtual machines that can be used as personal virtual desktops or virtual desktop pools by using RemoteApp and Desktop Connection. User accounts can be assigned a unique personal virtual desktop or be redirected to a virtual desktop pool where a virtual desktop is dynamically assigned. RD Virtualization Host is an important component to the Virtual Desktop Infrastructure (VDI) solution offered by Microsoft.
Why use Virtual Desktop Infrastructure?
The VDI solution includes the following scenarios:
Personal virtual desktops are specific virtual machines that are hosted on an RD Virtualization Host server that can be assigned to a user account in Active Directory Domain Services (AD DS) to use as a personal virtual desktop, which the user can then access by using RemoteApp and Desktop Connection or RD Web Access.
A virtual desktop pool is a group of identically configured virtual machines installed on an RD Virtualization Host server and managed through Hyper-V Manager. Users can access the virtual desktop pool through RemoteApp and Desktop Connection or RD Web Access. Because the virtual machines are identically configured, the user sees the same virtual desktop, regardless of which virtual machine in the virtual desktop pool the user connects to.
Virtual Desktop Infrastructure role services
The following role services are included in a typical VDI deployment:
RD Virtualization Host: RD Virtualization Host integrates with Hyper-V to host virtual machines and provide them to users as virtual desktops. You can assign a unique virtual desktop to each user in your organization, or provide them shared access to a virtual desktop pool.
An RD Virtualization Host server has the following functions:
Monitoring virtual machine guest sessions and reporting these sessions to the RD Connection Broker server.
Preparing the virtual machine for a remote desktop connection when requested by the RD Connection Broker server.
RD Session Host: The RD Session Host server running in redirection mode helps to securely redirect an RDP client connection to a virtual machine. When a user requests a virtual machine, the RD Session Host queries the RD Connection Broker server. The RD Connection Broker server then provisions a virtual machine for the user, and returns its IP address to the RD Session Host server. The RD Session Host server running in redirection mode will then redirect the RDP client to connect to the virtual machine by using the IP address.
RD Connection Broker: The main function of RD Connection Broker is to broker a user connection to an appropriate endpoint. Brokering of the connection involves:
Identifying the virtual machine for the user to make a remote connection.
Preparing the virtual machines for remote connections by communicating with the RD Virtualization Host server (for example, waking the VM from a saved state).
Querying the IP address of the virtual machine by communicating with the RD Virtualization Host server. This IP address is returned to the RD Session Host server running in redirection mode.
Monitoring user sessions in a virtual desktop pool scenario. A user with an existing session in a pool is redirected to the hosting virtual machine.
RD Web Access: RD Web Access provides users with an aggregated view of remote applications and desktop connections by using a Web browser. Using RD Web Access, a user can view all remote applications and virtual desktops (virtual desktop pools and personal virtual desktops) published to that user.
RD Licensing: RD Licensing manages the Remote Desktop Services client access licenses (RDS CALs) that are required for each device or user to connect to a virtual desktop. You use RD Licensing to install, issue, and track the availability of RDS CALs on a Remote Desktop license server.
RD Gateway: RD Gateway is an optional role service in the VDI deployment. RD Gateway enables authorized remote users to securely connect to resources on an internal corporate network, from any Internet-connected device.