func parseVlan(linkName string) (string, int, error) {
    // parse -o parent=eth0.10
    splitName := strings.Split(linkName, ".")
    if len(splitName) != 2 {
        return "", 0, fmt.Errorf("required interface name format is: name.vlan_id, ex. eth0.10 for vlan 10, instead received %s", linkName)