We support Knox within the Hive connector:
However, Knox is not supported for Radoop itself. Therefore, you can extract data from a Hadoop cluster with Knox,
but you cannot do in-cluster processing.
We do not have any further support because Knox changes the way you can connect to Hadoop.
The only way to connect Radoop to a Knox protected cluster is to use Rapidminer Server as a proxy; and thus go around Knox.