How to Install PHP-FPM with Nginx on Ubuntu 24.04

The following steps cover installing PHP-FPM and essential extensions, configuring Nginx to pass PHP requests to the FPM process manager, tuning PHP settings for production, and verifying the installation.

Installing PHP-FPM #

Unlike Apache’s embedded mod_php, Nginx does not process PHP natively. Instead, it delegates PHP requests to PHP-FPM (FastCGI Process Manager), a separate service that manages a pool of PHP worker processes. Nginx communicates with PHP-FPM through a Unix socket, passing each request and receiving the rendered output.

Install PHP-FPM and the CLI tools:

sudo apt update && sudo apt install -y php-fpm

This installs PHP 8.3 from the Ubuntu 24.04 (Noble Numbat) repositories along with the FPM process manager. The php8.3-fpm service starts automatically after installation.

Verify the PHP-FPM service is running:

sudo systemctl status php8.3-fpm

You should see active (running) in the output. PHP-FPM is now listening on a Unix socket at /run/php/php8.3-fpm.sock, ready to accept requests from Nginx.

Verifying the Installation #

Check the installed PHP version:

php -v

You should see output similar to:

PHP 8.3.x (cli) (built: ...)
Copyright (c) The PHP Group
Zend Engine v4.x.x, Copyright (c) Zend Technologies
    with Zend OPcache v8.3.x, Copyright (c), by Zend Technologies

Configuring Nginx for PHP #

Nginx needs to be told how to handle PHP files. Open the server block you created in the Nginx installation guide:

sudo nano /etc/nginx/sites-available/example.com

Replace the contents with the following configuration, which adds PHP processing and sets index.php as the default file:

server {
    listen 80;
    listen [::]:80;

    server_name example.com www.example.com;
    root /var/www/example.com;

    index index.php index.html index.htm;

    location / {
        try_files $uri $uri/ =404;
    }

    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php8.3-fpm.sock;
    }

    location ~ /\.ht {
        deny all;
    }
}

Save and exit (press CTRL + X, press Y, then press ENTER)

Here’s what each block does:

Test the configuration and reload Nginx:

sudo nginx -t && sudo systemctl reload nginx

Testing PHP Processing #

Create a PHP test file to verify Nginx passes requests to PHP-FPM correctly:

echo '<?php phpinfo(); ?>' | sudo tee /var/www/example.com/info.php

Open your browser and navigate to:

http://example.com/info.php

You should see the PHP information page. Look for the Server API row, which should show FPM/FastCGI, confirming that Nginx is correctly communicating with PHP-FPM.

Installing Common PHP Extensions #

Most web applications require additional PHP extensions. The following command installs a robust set of extensions needed by WordPress, Laravel, Drupal, and other popular frameworks:

sudo apt install -y php-mysql php-curl php-gd php-mbstring php-xml php-zip php-intl php-bcmath

Here’s what each extension provides:

Restart PHP-FPM to load the new extensions:

sudo systemctl restart php8.3-fpm

Verify the extensions are loaded:

php -m | grep -iE 'mysql|curl|gd|mbstring|xml|zip|intl|bcmath'

You should see each extension listed in the output.

Configuring PHP #

PHP-FPM has its own php.ini file, separate from the CLI version. The primary configuration file for PHP-FPM is:

/etc/php/8.3/fpm/php.ini

Common Configuration Changes #

Open the PHP-FPM configuration file:

sudo nano /etc/php/8.3/fpm/php.ini

Here are recommended settings for most web applications. Find each directive (use Ctrl + W to search) and modify as needed:

; Maximum memory a script can consume (increase for large applications)
memory_limit = 256M

; Maximum file upload size (adjust for media-heavy sites)
upload_max_filesize = 64M

; Maximum size of POST data (should be >= upload_max_filesize)
post_max_size = 64M

; Maximum script execution time in seconds
max_execution_time = 300

; Maximum time for parsing input data
max_input_time = 300

; Server timezone (important for date/time functions)
date.timezone = UTC

Save and exit (press CTRL + X, press Y, then press ENTER)

Restart PHP-FPM to apply configuration changes:

sudo systemctl restart php8.3-fpm

Production Error Handling #

In production, disable error display to prevent exposing sensitive information while still logging errors for debugging:

; Disable error display in browser (security)
display_errors = Off

; Log errors to file instead
log_errors = On

; Error log location (check Nginx's error log or set custom path)
; error_log = /var/log/php_errors.log

Save and exit (press CTRL + X, press Y, then press ENTER)

Important File Locations #

Key paths for managing PHP-FPM on Ubuntu 24.04 (Noble Numbat):

• PHP Configuration (FPM): /etc/php/8.3/fpm/php.ini — Primary settings file for web requests.
• PHP Configuration (CLI): /etc/php/8.3/cli/php.ini — Settings for command-line scripts (separate from FPM).
• FPM Pool Configuration: /etc/php/8.3/fpm/pool.d/www.conf — Worker process settings (pm.max_children, etc.).
• Additional Configuration: /etc/php/8.3/fpm/conf.d/ — Drop-in config files for extensions.
• FPM Socket: /run/php/php8.3-fpm.sock — Unix socket for Nginx-to-FPM communication.
• PHP-FPM Error Log: /var/log/php8.3-fpm.log — FPM process manager log.

Creating a Complete Test #

Create a simple PHP script to verify your setup works end-to-end. This replaces the Nginx test page you created earlier:

sudo nano /var/www/example.com/index.php

Add the following content:

<?php
$hostname = gethostname();
$php_version = phpversion();
$server_software = $_SERVER['SERVER_SOFTWARE'];
$document_root = $_SERVER['DOCUMENT_ROOT'];
?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>PHP Test - <?php echo $hostname; ?></title>
    <style>
        body { font-family: system-ui, sans-serif; max-width: 600px; margin: 50px auto; padding: 20px; }
        h1 { color: #4F5D95; }
        .info { background: #f4f4f4; padding: 15px; border-radius: 5px; margin: 10px 0; }
        .success { color: #28a745; }
        code { background: #e9ecef; padding: 2px 6px; border-radius: 3px; }
    </style>
</head>
<body>
    <h1>✓ PHP is Working!</h1>
    <div class="info">
        <p><strong>PHP Version:</strong> <code><?php echo $php_version; ?></code></p>
        <p><strong>Server:</strong> <code><?php echo $server_software; ?></code></p>
        <p><strong>Hostname:</strong> <code><?php echo $hostname; ?></code></p>
        <p><strong>Document Root:</strong> <code><?php echo $document_root; ?></code></p>
    </div>
    <p class="success">Your LEMP stack's PHP component is configured correctly.</p>
    <p><small>Return to <a href="https://devanswers.net/series/lemp-stack/">LEMP Stack Documentation</a></small></p>
</body>
</html>

Save and exit (press CTRL + X, press Y, then press ENTER)

Visit http://example.com in your browser to see the test page. If you see the PHP version and server details, your LEMP stack’s PHP layer is working correctly.

Conclusion #

You now have PHP 8.3 running as PHP-FPM with Nginx on Ubuntu 24.04, complete with essential extensions for modern web applications.