The osg Roll can be installed during the Frontend installation or added to a running frontend. In either case, client nodes must be (re)installed.
The osg Roll is added to a Frontend installation in exactly the same manner as the required HPC Roll. Simply select the osg roll as you would any network- or CD-based roll. Specifically, after the HPC Roll is added the installer will once again ask if you have a Roll (see below). Select 'Yes' and insert the osg Roll.
Once the osg Roll is loaded the installer will continue installation automatically with no further user input. Other appliances can be made part of the execution pool through setting an appliance attribute and reinstalling those nodes.