qadministrator operation not authorized

I'm trying to create a small cluster of a few MacPro machines at work. However, once I get the cluster all set up in Qadministrator with the controller properly set and everything, I get an error that says the following:

Alert

Error occurred while creating new cluster:

SwampDaemon::NFSPublisher: operation not

authorized

I've tried making any of the three machines the controller, and doing the setup on all three of them, but I get this error on each one. Any clues?