When Mac Locking is enabled at the port level there are two settings to be concerned about. The first is the number of dynamically locked Mac addresses. The default setting of 600 in Policy Manager allows up to 600 MAC addresses to come into the port as "First Arrival" addresses. These may be moved to static by a single button push or by manually adding them to the table. Once you've learned all the mac addresses that you want on a port and have pushed them to Static, you can set dynamic to zero. Once the zero value is applied, this will only allow the statically locked macs on the port. Any others that try to come in will not be learned and their traffic discarded. The other setting is the number of statically locked MAC addresses allowed on this device type and the range is controlled through the port properties screen. We expect our video to be up on youtube within 24 hours to demonstrate this functionality and showing the screens where these settings are configured. A MAC address should only show up once in the Locked Mac Address table. Please make sure that both your firmware and Netsight versions are up to date. If they are and the problem persists, we'll want to pursue this behavior further via a GTAC case.