Stop Press: recent improvements to the check_netapp_pro suite of programs have enabled the removal of certain redundant cluster-mode parameters and functions, as well as reducing the configuration effort required for the checks, creating a more efficient source codebase which is easier to use. The --node parameter to check_netapp_cluster.pl was a concern as it required the admin to know the node-names in advance, something that was not always possible or desirable. So the code checking the cf-status has been moved to the legacy check_netapp7_cluster and into check_netapp_takeover for cluster-mode (cdot) devices.
Half a year ago there was very little demand for Nagios plugins that support Cluster Mode. Recently, we have received more and more requests for just such plugins. We are looking at Q4 2013 to launch our new release of Nagios Plugins for NetApp, Version 3.0, with added support for cluster mode.