As you might know connecting to a RDS environment running on Windows Server 2012 (R2) requires users to always connect to the (farm of) RD Connection Broker Servers initially, from where they will be redirected to a RD Session Host in a farm. In order for the RD Connection Broker to be able to redirect the session to the correct RD Session Host farm it needs to be aware of the Session Collection. More info, also sees RD Connection Broker HA and the RDP properties on the client.
DellWyse ThinOS version 8 comes with a full featured RDP8 client and supports the RD Connection Broker 2012. To connect ThinOS8 to a Windows Server 2012 RDS environment you can specify the following .ini parameters;
VDIBroker=https://rds.domain.com AutoConnectList="Full Desktop"
The parameter VDIBroker should point to your RD Connection Broker Server(s) and optionally you can use AutoConnectList to auto run a certain Remote App or Full Desktop. The parameter ConnectionBroker specifies that the broker is a Microsoft RD Connection Broker. Setting the parameter SignOn to Yes allows Thin OS to pass the login credentials, entered when logging on the Thin Client, to the RD Connection Broker
If a user is authorized for multiple Session Collections within a single deployment ThinOS8 will retrieve and show all authorized Remote Apps and Desktops from all Session Collections combined together.
More info: http://www.wyse.com/products/cloud-clients/firmware/Wyse-Zero-and-Wyse-ThinOS