def change_vlan_id(self, vlan_id):
        """
        Change a VLAN id for an inline interface.
        
        :param str vlan_id: New VLAN id. Can be in format '1-2' or
            a single numerical value. If in '1-2' format, this specifies
            the vlan ID for the first inline interface and the rightmost
            for the second.
        :return: None
        """
        first, second = self.nicid.split('-')
        firstintf = first.split('.')[0]
        secondintf = second.split('.')[0]
        newvlan = str(vlan_id).split('-')
        self.update(nicid='{}.{}-{}.{}'.format(
            firstintf, newvlan[0], secondintf, newvlan[-1]))