Request filtering

Hi All

I'm yet to implement Request Filtering on a large scale and have up to this point been mainly using URLScan where this level of filtering is required.

I would now like to implement Request Filtering across a number of production web servers but am very nervous about doing so because each server hosts many different production websites. URLScan had a feature where you could configure the tool in listen only mode (RejectResponseUrl=/~*). Does anyone know whether there is equivalent functionality in the Request Filtering module?

Thanks!