In moving to the latest version of our McAfee Endpoint Storage Protection (our off-box antivirus solution for CIFS on NetApp), we experienced a problem where the McAfee product would work for a few days and then disconnect. This routinely occurred on both of our McAfee antivirus servers. After attempting multiple things from the McAfee side, their tech pointed me to a NetApp article that described our exact behavior.
I downgraded the NetApp 1.0.5 product to 1.0.4P1 and everything has been working since. From memory, I did try using a Management LIF with the 1.0.5 product, but I wasn't able to configure it without getting an error.