[Tutorials] [Remote Desktop Session Host] – Published Dec 2011

Licensing is always a painful topic; Remote Desktop Services are no exception to this rule.  To make things worse, a Remote Desktop Session Host server may work perfectly well right after installation, but stop doing its job after a couple of months – due to licensing issues.  This is why it is critically important to fully understand the concepts of Remote Desktop Services licensing.

When you purchase the Windows Server 2008 R2 operating system, the server license is included.  Technically, this license is represented by a unique license key.  It allows you to install and operate Windows Server 2008 R2.  You will be asked for this license key when installing or activating the operating system.  In addition to that, every computer or terminal that establishes a connection to Windows Server 2008 R2 requires a Client Access License or a CAL.  This license permits clients to use the file, print, or other network services provided by a Windows Server.

Only client computers or Windows terminals with a valid Windows Server 2008 R2 Remote Desktop Services Client Access License – RDS CAL for short – are allowed to access a Windows Server 2008 R2 Remote Desktop Session Host server.  An RDS CAL is needed to initiate a remote session and launch Windows applications on the server.

NOTE: For administrative purposes, two simultaneous interactive remote connections are permitted that do not require RDS CALs.  This behavior is hard-coded into the operating system core, you cannot change it.

Similar to the Client Access License, the Remote Desktop Services Client Access License is available “Per Device” or “Per User”.

• A Per Device license is associated with a device which is defined as a unique piece of hardware used to connect to a server.  If this licensing mode is selected, each computer device connecting to a Remote Desktop Session Host server must have such a license.  When Per Device licensing is selected, different devices always need separate licenses even if they are never used at the same time.
• A Per User license grants a user associated with a user account an access license for any client device.  The user can then access the company’s Remote Desktop Session Host servers from his or her office workstation or hand-held device, from a notebook on the road, or from a personal computer from home.  Two different users cannot share such a license even if they use the same physical computer and never log in at the same time.

It is possible to mix the two license types so that both are provided through a Remote Desktop Licensing server.  A Remote Desktop Session Host server, in contrary, can only be either in Per Device or in Per User licensing mode, which means that licensing modes cannot be mixed there.  However, if multiple RD Session Host servers are being used in one network, some of them can be in Per Device licensing mode while others are in Per User licensing mode.

The good news is that it is possible to try out Remote Desktop Services before a permanent license is required.  An RD Session Host server can grant non-licensed clients connectivity for 120 days.  After this time, the RD Session Host server stops allowing these clients to connect unless a Remote Desktop Licensing server is available in the network.

A Remote Desktop Licensing server that is not yet activated can issue temporary Per Device licenses valid for 90 days.  After the combined evaluation period of up to 120 plus 90 days, clients can connect to a Remote Desktop Session Host server only after they received a valid permanent license from an activated Remote Desktop Licensing server.  This implies that before a Remote Desktop Licensing server is able to distribute permanent RDS CALs it must be activated.

[Tutorials] [Remote Desktop Session Host]