Master Caddy 2: Install, Configure, and Integrate PHP for Fast Web Hosting

Installation

The official installation guide is available at https://caddyserver.com/docs/install. On Debian‑based systems you can install Caddy with the following commands:

sudo apt install -y debian-keyring debian-archive-keyring apt-transport-https curl
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo gpg --dearmor -o /usr/share/keyrings/caddy-stable-archive-keyring.gpg
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' | sudo tee /etc/apt/sources.list.d/caddy-stable.list
sudo apt update
sudo apt install caddy

Verify Service Startup

Use the following commands to control the Caddy service:

systemctl start caddy
caddy start
caddy run # Starts server and blocks indefinitely

systemctl stop caddy
caddy stop

systemctl reload caddy
caddy reload

systemctl restart caddy
caddy stop && caddy start

Enable the service to start on boot:

sudo systemctl daemon-reload
sudo systemctl start caddy.service
sudo systemctl enable caddy.service

Configuration

Caddy works on many Linux distributions. After installation the default global configuration file is /etc/caddy/Caddyfile. Individual site configurations can be placed in /etc/caddy/conf/, mirroring the Apache/Nginx layout:

/etc/caddy
  ├── Caddyfile
  └── conf/
      └── caddy.tinywan.com.conf

Primary Configuration (Caddyfile)

{
    log default {
        format console
        output file /var/log/caddy/system.log
        exclude http.log.access
    }
}
import conf/*

Site‑Specific Configuration Example

caddy.tinywan.com {
    # Set the document root for this site
    root * /home/www/website/caddy

    # Enable static file serving
    file_server
}

Applications

Static Site Hosting

caddy.tinywan.com {
    root * /home/www/website/caddy
    file_server
}

Access the site at https://caddy.tinywan.com/. The default Caddy welcome page will appear, which can be replaced with a custom HTML page.

Reverse Proxy

proxy-caddy.tinywan.com {
    reverse_proxy localhost:6140
}

HTTP Redirect to www Subdomain

tinywan.com {
    redir https://www.{host}{uri}
}

www.tinywan.com {
    root * /home/www/website/full-stack/dist
    file_server
}

Requests to tinywan.com are redirected to https://www.tinywan.com/.

PHP‑FPM Integration

Caddy uses FastCGI reverse proxy to hand PHP requests to PHP‑FPM, similar to Apache or Nginx.

caddy-php.tinywan.com {
    # Document root for the PHP application
    root * /home/www/website/demo/public

    file_server
    encode gzip

    # Forward .php requests to the PHP‑FPM socket
    php_fastcgi unix//var/run/php8.0.7-fpm.sock
}

If you encounter a 502 Bad Gateway error, check the Caddy error log for permission issues on the PHP‑FPM socket. Adjust the service user and group in /lib/systemd/system/caddy.service from caddy to www (or another appropriate user) and reload the service.

Testing PHP

Create /home/www/website/demo/public/index.php with the following content:

<?php
echo "Hello 开源技术小栈";

Visit https://caddy-php.tinywan.com/ (ensure DNS resolves to the server) to see the PHP output.