So put it in the nginx settings (settings of your site):
error_log /var/log/nginx/nginx_error.log warn;
And this is how your site’s Apache settings:
ErrorLog /var/log/httpd/error_log
So you will display errors in a separate file and you can see the error and fix it.
I can also advise for nginx to increase the size of the request, or rather the size of the body:
client_max_body_size 8M;
This must be entered in the /etc/nginx/nginx.conf file. For php, you can do the same thing.
upload_max_filesize = 40M // для файла post_max_size = 40M // для запроса
It is necessary to enter in the file / etc / php / <your version of php> /apache2/php.ini
Well, this is naturally the original things. We must first smoke logs.