FPM

The FPM variation runs PHP-FPM (FastCGI Process Manager) without a web server. It's designed to work alongside a separate web server or load balancer that handles static content and proxies PHP requests to this container.

Use this variation when you're building microservices architectures or have a separate proxy layer handling HTTP traffic.

When to Use FPM

Use the FPM variation when you need to:

• Separate your PHP processing from your web server layer
• Build microservices where PHP runs as a dedicated backend service
• Use a separate load balancer or API gateway to route traffic
• Have an existing NGINX, Traefik, or other reverse proxy infrastructure
• Scale your PHP processing independently from your web server

Perfect for

• Microservices architectures where separation of concerns is important
• Kubernetes deployments with separate service containers
• Large-scale deployments with dedicated load balancers
• Advanced setups where you want full control over your proxy configuration

What's Inside

How FPM Works

Unlike variations that include a web server, the FPM variation only runs PHP-FPM, which listens on port 9000 for FastCGI requests.

You'll need a separate web server (like NGINX, Apache, or Caddy) to:

This architecture gives you maximum flexibility but requires more configuration than the all-in-one variations.

Quick Start

Here are a few examples to help you get started with the FPM variation.

Docker Compose with Separate NGINX

This example shows a common setup with PHP-FPM in one container and NGINX in another.

services:
  php:
    image: serversideup/php:8.4-fpm
    volumes:
      - ./:/var/www/html

  nginx:
    image: nginx:alpine
    ports:
      - "80:80"
    volumes:
      - ./:/var/www/html
      - ./nginx.conf:/etc/nginx/conf.d/default.conf
    depends_on:
      - php

And your NGINX configuration (nginx.conf):

server {
    listen 80;
    server_name localhost;
    root /var/www/html/public;

    index index.php index.html;

    location / {
        try_files $uri $uri/ /index.php?$query_string;
    }

    location ~ \.php$ {
        fastcgi_pass php:9000;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }
}

Health Check

The FPM variation includes php-fpm-healthcheck, a POSIX-compliant script that monitors PHP-FPM's /status endpoint to verify the service is healthy.

services:
  php:
    image: serversideup/php:8.4-fpm
    volumes:
      - ./:/var/www/html
    healthcheck:
      test: ["CMD", "php-fpm-healthcheck", "--listen-queue=10"]
      interval: 10s
      timeout: 3s
      retries: 3

Environment Variables

The FPM variation supports extensive customization through environment variables. Here are some common ones:

Performance Tuning

The FPM variation gives you fine-grained control over PHP process management. Here are some tuning tips:

For High-Traffic Applications

services:
  php:
    image: serversideup/php:8.4-fpm
    environment:
      PHP_FPM_PM_CONTROL: "static"
      PHP_FPM_PM_MAX_CHILDREN: "50"
      PHP_MEMORY_LIMIT: "512M"

For Low-Memory Environments

services:
  php:
    image: serversideup/php:8.4-fpm
    environment:
      PHP_FPM_PM_CONTROL: "ondemand"
      PHP_FPM_PM_MAX_CHILDREN: "10"
      PHP_FPM_PM_PROCESS_IDLE_TIMEOUT: "10s"

Further Customization

If you need to customize the container further, reference the docs below:

• Environment Variable Specification - See which environment variables are available to customize PHP and PHP-FPM settings.
• Command Reference - See which commands are available to run inside the container.