How to set php ini settings in nginx config for just one host

Question

One can set error_reporting in nginx.conf like so:

fastcgi_param   PHP_VALUE   error_reporting=E_ALL;

But if I do this in one server block, will it affect all the others as well? Should I change php settings in all server blocks simultaneously?

Answer 1

You can set PHP_VALUE per server and this will affect that server only. If you need equal PHP_VALUE for all your servers with PHP, use include files.

For example (debian), create /etc/nginx/conf.d/php_settings.cnf:

fastcgi_param PHP_VALUE "upload_max_filesize=5M;\n error_reporting=E_ALL;";

Then include this file into any server or location config you need:

server {
  ...
  location ~ \.php$ {
    ...
    include /etc/nginx/conf.d/php_settings.cnf;
  }
  ...
}

Answer 2

If every host on your server runs in its own PHP-FPM pool, than adding fastcgi_param PHP_VALUE ... to one nginx host will not affect the other ones.

If on the other hand all nginx hosts use one PHP-FPM pool, you should specify PHP_VALUE for every host you have (error_reporting=E_ALL for one of them, empty value for others). Since fastcgi_param passes PHP_VALUE if specified, and doesn't pass if not. In a while all workers will have PHP_VALUE=error_reporting=E_ALL, unless you explicitly set PHP_VALUE in other hosts.

Additionally, fastcgi_param PHP_VALUE ... declarations override one another (the last one takes effect).

Steps to reproduce:

1. apt install nginx php5-fpm

2. /etc/nginx/sites-enabled/hosts.conf:

   server {
       server_name  s1;
       root  /srv/www/s1;
       location = / {
           include  fastcgi.conf;
           fastcgi_pass unix:/var/run/php5-fpm.sock;
           fastcgi_param  PHP_VALUE  error_reporting=E_ERROR;
       }
   }
   
   server {
       server_name  s2;
       root  /srv/www/s1;
       location = / {
           include  fastcgi.conf;
           fastcgi_pass  unix:/var/run/php5-fpm.sock;
       }
   }
   

3. Add s1, s2 to /etc/hosts

4. Change pm to static, pm.max_children to 1 in /etc/php5/fpm/pool.d/www.conf

5. cat /srv/www/s1/index.php:

   <?php var_dump(error_reporting());
   

6. systemctl restart php5-fpm && systemctl restart nginx

7. curl s2 && curl s1 && curl s2

   int(22527)
   int(1)
   int(1)