def METHOD_NAME(iface, iface_type=None):
    """
    Shutdown a network interface
    CLI Example:
    .. code-block:: bash
        salt '*' ip.down eth0
    """
    # Slave devices are controlled by the master.
    if iface_type not in ["slave"]:
        return __salt__["cmd.run"]("ip link set {} down".format(iface))
    return None