the problem is caused because group 210000, the remote broadcast group, is configured twice from two different methods. One that correctly configures the Vlan port in the group, (1) setupStandardElanBroadcastGroups, and one that does not, (2) setElanBCGrouponOtherDpns. Both of these functions are invoked "up stack" from ElanInterfaceManager.addElanInterface (though (2) is called in a worker and thus in a different thread -InterfaceAddWorkerOnElanInterface). This function (2) only adds ports that are Vxlan ports (so in this case no ports) and then pushes the group to the switch which many times (threading) overwrites the original group written by (1).