Problems with move_uploaded_file

very good afternoon! it happens that I am moving a file loaded, but at the moment of seeing on the server the file does not move! the problem is that yesterday if it worked, but because of problems I have to change the server, however the new server has the same characteristics in which it has PHP 5.6.

the code I am using is (code fragment):

$fecha = Date('Y-m-d-H-i-s');
$ruta = "../view/tmp_files/";
// renombra el archivo con la información anterior
$archivo = $fecha."-".$_FILES['excel']['name'];
// mueve el archivo a la ruta ingresada
//echo "$ruta$archivo";
if (move_uploaded_file($_FILES['excel']['tmp_name'], "$ruta$archivo")) {
    echo "ok";
}else {
    echo "fail";
}

however the tmp_files folder has the appropriate permissions 777

I hope someone knows what is happening and can help me.

Greetings.

PDT: the server is a CentOS 7