Managing Multiple PHP Versions on Your Server

Why Multiple PHP Versions?

Different applications may require different PHP versions. WordPress might run best on 8.2, while a legacy app needs 7.4. Running multiple versions lets you host them all on one server.

Install Multiple Versions

sudo add-apt-repository ppa:ondrej/php -y
sudo apt update

# Install PHP 7.4 and 8.2
sudo apt install -y php7.4-fpm php7.4-mysql php7.4-mbstring php7.4-xml
sudo apt install -y php8.2-fpm php8.2-mysql php8.2-mbstring php8.2-xml

Nginx Per-Site PHP Version

# Site using PHP 8.2
server {
    server_name modern-app.com;
    location ~ \.php$ {
        fastcgi_pass unix:/run/php/php8.2-fpm.sock;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $realpath_root$fastcgi_script_name;
    }
}

# Site using PHP 7.4
server {
    server_name legacy-app.com;
    location ~ \.php$ {
        fastcgi_pass unix:/run/php/php7.4-fpm.sock;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $realpath_root$fastcgi_script_name;
    }
}

CLI Version Switching

# Set default CLI version
sudo update-alternatives --set php /usr/bin/php8.2

# Or use full path
/usr/bin/php7.4 script.php
/usr/bin/php8.2 script.php

Per-Version Configuration

Each version has its own php.ini:

/etc/php/7.4/fpm/php.ini
/etc/php/8.2/fpm/php.ini