session wiped out between pages

I’m making a login page and for some reason the session will not persist between where I set it and the page where I am forwarding to. I can comment out the header in the page where the session was initialized and see that the session has the data in it. However, when I do a print_r in the target page, the session is empty.

I have already made sure that session_start is called. There is only one domain for this site and my browser is set to accept cookies. I can forward to any other page and see the session data but just not this one.

Is there something that someone can offer to help in debugging this?

$_SESSION['auth'] = $auth;
header( "Location: /" ); // commenting this out shows the data is in fact there

I want to protect the index page so I test to see if session[‘auth’] is set. If not, I forward over to /user/login which allows the user to login. If successful then we forward back over to the index page where it should pass the isset session test. It fails though and there is no session data.

Answer

set.php:

session_start();
$_SESSION['auth'] = true;

header('Location: /');

index.php:

session_start();

var_dump($_SESSION);

Create these 2 files and request set.php. What do you see?