Set up the repository for Caddy and install
$ sudo echo "deb [trusted=yes] https://apt.fury.io/caddy/ /" | sudo tee -a /etc/apt/sources.list.d/caddy-fury.list
$ sudo apt update
$ sudo apt install caddy
Install PHP
$ sudo apt install php7.4-fpm php7.4-cli php7.4-gd php7.4-xml php7.4-zip php7.4-mbstring php7.4-curl
Optionally install MySQL (MariaDB)
$ sudo apt install mariadb-server mariadb-client php7.4-mysql
Configure and secure MariaDB
$ sudo mysql_secure_installation
You will be asked the following:
Enter current password for root (enter for none):
Set root password? [Y/n] y
Remove anonymous users? [Y/n] y
Disallow root login remotely? [Y/n] y
Remove test database and access to it? [Y/n] y
Reload privilege tables now? [Y/n] y
Make sure Caddy, PHP-FPM and MariaDB start automatically
$ sudo systemctl enable caddy
$ sudo systemctl enable php7.4-fpm
$ sudo systemctl enable mariadb
Set up your system users and create a directory to hold their websites. We’ll start with two but you can add more later
$ sudo useradd user1
$ sudo mkdir -p /home/user1/www; chown user1:user1 /home/user1/www; chmod +x /home/user1
$ sudo useradd user2
$ sudo mkdir -p /home/user2/www; chown user2:user2 /home/user2/www; chmod +x /home/user2
Modify your /etc/caddy/Caddyfile to contain the following:
http://user1.example.com {
root * /home/user1/www
encode gzip
file_server
php_fastcgi unix//var/run/php/user1.socket {
split .php
index index.php
}
}
http://user2.example.com {
root * /home/user2/www
file_server
encode gzip
php_fastcgi unix//var/run/php/user2.socket {
split .php
index index.php
}
}
*Be careful of the syntax in the Caddyfile. The file must start with a “virtual host” block. If there is more than one virtual host, make sure they are all defined within their own section i.e. domain.com { definitions } After modifying your Caddyfile, you can check the syntax of the file with $ caddy validate /etc/caddy/Caddyfile
Now we need to set up our individual PHP-FPM pools.
/etc/php/7.4/fpm/pool.d/user1.conf
[user1]
user = user1
group = user1
listen.owner = caddy
listen.group = caddy
listen.mode = 0660
listen = /var/run/php/user1.socket
pm = dynamic
pm.max_children = 5
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
/etc/php/7.4/fpm/pool.d/user2.conf
[user2]
user = user2
group = user2
listen.owner = caddy
listen.group = caddy
listen.mode = 0660
listen = /var/run/php/user2.socket
pm = dynamic
pm.max_children = 5
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
Reload php-fpm and Caddy to load our changes
$ sudo systemctl reload php7.4-fpm
$ sudo systemctl restart caddy
Allow http and https through the firewall
$ sudo ufw allow http
$ sudo ufw allow https