How to implement PHP-FPM process isolation and resource limits in Nginx?

To implement PHP-FPM process isolation and resource limits in Nginx, you can follow these steps:

Step 1: Install and configure PHP-FPM

Install PHP and PHP-FPM on your server if not already installed.
Edit the PHP-FPM configuration file (php-fpm.conf or www.conf) and set the following options:
- Set the user and group parameter to a non-privileged user and group.
- Set the listen.allowed_clients parameter to allowed IP addresses or remove it to allow connections from any IP.
- Configure other PHP-FPM options as per your requirements.

Step 2: Configure Nginx to use PHP-FPM

Edit the Nginx configuration file (nginx.conf or a specific site configuration file) and add the following location block to handle PHP files:

location ~ \.php$ {
   fastcgi_pass   127.0.0.1:9000;   // This should match the PHP-FPM listen address
   fastcgi_index  index.php;
   fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
   fastcgi_param  PATH_INFO $fastcgi_path_info;
   include        fastcgi_params;
}

Restart or reload Nginx to apply the changes.

Step 3: Set PHP-FPM process isolation and resource limits

Edit the PHP-FPM configuration file (php.ini) and set the following options to enable process isolation and resource limits:
- Set php_admin_value[rlimit_files] and php_admin_value[rss] to limit the number of open files and memory usage respectively. For example:
php_admin_value[rlimit_files] = 1024 php_admin_value[rss] = 128M
- Set pm (process manager) options to control the maximum number of PHP-FPM processes, maximum requests per process, etc. For example:
pm = static pm.max_children = 5 pm.max_requests = 500
Restart or reload the PHP-FPM service to apply the changes.

With these steps, you have implemented PHP-FPM process isolation and resource limits in Nginx.