Cameron Fuller said it best “Even when you spend years working on a specific technology occasionally you are pleasantly surprised to find out that something already exists in the product but you are unaware of it.”

He has written an article which is available here which describes the use of the /SiteName switch when approving a gateway in order to automatically create and populate a group containing all devices being managed by that gateway.

This is certainly a useful feature.

Note – If you use the /sitename switch then bookmark this article by Brian McDermott – How to remove an OpsMgr 2012 Gateway Server that is associated with a site to prevent some future headaches.