remove the configured prefix on a border router

        Args:
            prefixEntry: a on-mesh prefix entry

        Returns:
            True: successful to remove the prefix entry from border router
            False: fail to remove the prefix entry from border router

def removeRouterPrefix(self, prefixEntry):
        """remove the configured prefix on a border router

        Args:
            prefixEntry: a on-mesh prefix entry

        Returns:
            True: successful to remove the prefix entry from border router
            False: fail to remove the prefix entry from border router
        """
        print '%s call removeRouterPrefix' % self.port
        print prefixEntry
        prefix = self.__convertIp6PrefixStringToIp6Address(str(prefixEntry))
        try:
            prefixLen = 64
            cmd = 'prefix remove %s/%d' % (prefix, prefixLen)
            print cmd
            if self.__sendCommand(cmd)[0] == 'Done':
                # send server data ntf to leader
                return self.__sendCommand('netdataregister')[0] == 'Done'
            else:
                return False
        except Exception, e:
            ModuleHelper.WriteIntoDebugLogger("removeRouterPrefix() Error: " + str(e))