500 false revelations from PHP Nginx

Now in a program, passed a session_id after the return Nginx 500 error. Passing another session_id will not be an error, and will not be known until debug mode is turned on. Because PHP syntax error, and in PHP.ini closed the display_error, and in the program to close the error message, so directly returned 500 error to nginx.

This parsing is in the PHP-FPM documentation:

If the php script being accessed contains a syntax error, and Display_errors is set to false, and there is no further setting, it returns "http/1.0 Internal Server Error" immediately. If you need to set an error code that is different from 500 (already used in many cases). Or if you want to make this behavior independent of the display_errors settings, you can use Fastcgi.error_header. If you use php-5.2.5 or above and php-fpm at the same time, the priority of the Fastcgi.error_header is higher.

This problem is resolved by finding the problem after you turn on debug mode.

Here are some revelations: some problems seem to occur in a module, and its origin may be related to modules in that module. In the event of this problem, we must trace the source and break it!

500 false revelations from PHP Nginx