[Internal 500 Error in `error.log` on Nginx]

I am using the Nginx server on ISPconfig. When I get an Internal 500 error, I can't see the error in the error.log file. I was using Apache before and could see errors, Nginx unfortunately I can't see it. I honestly don't know very well about Nginx.

I currently have an Error 500 but I can't find where the error is.

The file is empty;

Quote

tail -f /var/log/ispconfig/httpd/example.com/error.log

What can I do to be able to log the 500 Error?

PHP 7.4 PHP-FPM - Nginx 1.14.2

[Session information sharing on different subdomains]

1 minute ago, requinix said:

If you're sure that the user can browse the other site perfectly fine, with the same session information as the first site, then the problem will be somewhere in the code that gets the member ID and stores it in the database...

 

Yes, I'm sure because without logging in, the application running on the subdomain cannot be accessed. Anyway, I'll keep researching, thanks for your help.

[Session information sharing on different subdomains]

1 hour ago, requinix said:

You talk about a member ID not being "registered" and post some code that deals with session cookies. I have no idea if the two things are supposed to be related.

When the page on the second subdomain handles the form data, either it can access the session data or it cannot. If it can't then you have cookie and/or session data problems, and if it can then you have some problem getting the ID into the database (I guess?). It's hard to tell without knowing your application(s) and having a more detailed explanation of what you're seeing and what you expected to see.

Yes, I realized I spelled it wrong. I meant that the member's ID is not saved with the form data in the database. Although the member's session is active, it does not see the member's ID when POSTing to the other subdomain.
While the `a.example.com` member logs in and can use the `b.example.com` site without any problems since he logs in; Unfortunately, the information of the member is not recorded in the form submission among the subdomains, but when the member logs in, the session are active in all subdomains.

[Session information sharing on different subdomains]

I am sharing sessions between two subdomains and I can see the member's information in their different subdomains. If the member logs out, all subdomains are logged out. All is good so far.

However, for example, a.example.com the form information is POSTed to b.example.com. This form information is saved in the database, but the member's ID is not registered. No information is registered to the database with the member. What could be the reason for this?

    ini_set('session.cookie_domain',
    substr($_SERVER['SERVER_NAME'], strpos($_SERVER['SERVER_NAME'], "."), 100));
    setcookie("MID", $_SESSION['uID'], 60 * 60 * 24 * 100, '/', '.example.com');
    session_set_cookie_params(60 * 60 * 24 * 100, '/', '.example.com', false, false);
    ini_set('session.save_path', $pathStorageMembers . 'sessions');
    ini_set('session.cookie_lifetime', 60 * 60 * 24 * 100);
    ini_set('session.gc_maxlifetime', 60 * 60 * 24 * 100);
    session_start();

Thank you.