Install a LEMP Stack on Debian 9

What is a LEMP Stack?

This guide describes an alternative to the popular LAMP stack, known as LEMP. The LEMP stack replaces the Apache web server component with NGINX, providing the E in the acronym: Linux, NGINX, MySQL/MariaDB, PHP.

Before You Begin

• You will need root access to your Linode, or a user account with sudo privilege.
• Set your system’s hostname.
• Update your system.

Installation

NGINX

These instructions install NGINX Mainline on Debian 9 from NGINX Inc’s official repository. For other distributions, see the NGINX admin guide. For information on configuring NGINX for production environments, see our Getting Started with NGINX series.

1. Open /etc/apt/sources.list in a text editor and add the following line to the bottom:

   File: /etc/apt/sources.list

   1	deb http://nginx.org/packages/mainline/debian/ stretch nginx

2. Import the repository’s package signing key and add it to apt:

   sudo wget http://nginx.org/keys/nginx_signing.key
   sudo apt-key add nginx_signing.key
   

3. Install NGINX:

   sudo apt update
   sudo apt install nginx
   

4. Ensure NGINX is running and enabled to start automatically on reboots:

   sudo systemctl start nginx
   sudo systemctl enable nginx
   

MariaDB

1. Install the MariaDB server and MySQL/MariaDB-PHP support. You may be prompted to set a root password during installation:

   sudo apt install mariadb-server php7.0-mysql
   

2. Ensure MariaDB is running and enabled to start automatically on reboot:

   sudo systemctl start mariadb
   sudo systemctl enable mariadb
   

3. Run the mysql_secure_installation script.

   sudo mysql_secure_installation
   

   If you were not prompted to create a MySQL root user password when installing MariaDB, press Y when prompted.

   Answer Y at the following prompts:

   • Remove anonymous users?
   • Disallow root login remotely?
   • Remove test database and access to it?
   • Reload privilege tables now?

4. Log in to MariaDB’s SQL shell. Enter the root user’s password when prompted:

   mysql -u root -p
   

5. Create a test database and user with access permission. Replace testdb and testuser with appropriate names for your setup. Replace password with a strong password:

   CREATE DATABASE testdb;
   CREATE USER 'testuser' IDENTIFIED BY 'password';
   GRANT ALL PRIVILEGES ON testdb.* TO 'testuser';
   quit
   

PHP

1. Install the PHP FastCGI Processing Manager, which will bring in the core PHP dependencies:

   sudo apt install php7.0-fpm
   

2. Tell PHP to only accept URIs for files which actually exist on the server:

   sudo sed -i 's/;cgi.fix_pathinfo=1/cgi.fix_pathinfo=0/g' /etc/php/7.0/fpm/php.ini
   

3. Ownership of PHP’s listening UNIX sockets is set to www-data by default, but they need to match the user and group NGINX is running as. If you installed NGINX from the NGINX repository as in the steps above, NGINX will be using the nginx user and group.

   Change the listen variables in www.conf to that:

   sudo sed -i 's/listen.owner = www-data/listen.owner = nginx/g' /etc/php/7.0/fpm/pool.d/www.conf
   sudo sed -i 's/listen.group = www-data/listen.group = nginx/g' /etc/php/7.0/fpm/pool.d/www.conf
   

Set an NGINX Site Configuration File

1. Create the site’s root directory where its content will live. Replace example.com with your site’s domain:

    sudo mkdir -p /var/www/example.com/
   

2. Rename the default example site configuration provided with the package. This disables it. Or if you have no use for it, delete it:

   sudo mv /etc/nginx/conf.d/default.conf /etc/nginx/conf.d/default.conf.disabled
   

3. Website configuration files should be kept in /etc/nginx/conf.d/. Create a configuration file for your site. Again replace example.com with your site’s domain:

   File: /etc/nginx/conf.d/example.com.conf

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   server { listen 80 default_server; listen [::]:80 default_server; server_name example.com www.example.com; root /var/www/example.com; index index.html; location / { try_files $uri $uri/ =404; } location ~* \.php$ { fastcgi_pass unix:/run/php/php7.0-fpm.sock; include fastcgi_params; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; fastcgi_param SCRIPT_NAME $fastcgi_script_name; } }

   Here’s a breakdown of the server block above:

   • NGINX is listening on port 80 for incoming connections to example.com or www.example.com.

   • The site is served out of /var/www/example.com/ and its index page (index.html) is a simple .html file. If your index page will use PHP, substitute index.php for index.html.

   • try_files tells NGINX to verify that a requested file or directory actually exists in the site’s root filesystem before further processing the request. If it does not, it returns a 404.

   • location ~* \.php$ means that NGINX will apply this configuration to all .php files (file names are not case sensitive) in your site’s root directory, including any subdirectories containing PHP files.

   • The * in the ~* \.php$ location directive indicates that PHP file names are not case sensitive. This can be removed if you prefer to enforce letter case.

   • fastcgi_pass specifics the UNIX socket where PHP listens for incoming connections from other local processes.

   • include fastcgi_params tells NGINX to process a list of fastcgi_param variables at /etc/nginx/fastcgi_params.

   • The fastcgi_param directives contain the location (relative to the site’s root directory) and file naming convention of PHP scripts to be served when called by NGINX.

Test the LEMP Stack

1. Restart PHP and reload the NGINX configuration:

   sudo systemctl restart php7.0-fpm
   sudo nginx -s reload
   

2. Create a test page to verify NGINX can render PHP and connect to the MySQL database. Replace the testuser and password fields with the MySQL credentials you created above.

   File: /var/www/example.com/test.php

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   <html> <head> <h2>LEMP Stack Test</h2> </head> <body> <?php echo '<p>Hello,</p>'; // Define PHP variables for the MySQL connection. $servername = "localhost"; $username = "testuser"; $password = "password"; // Create a MySQL connection. $conn = mysqli_connect($servername, $username, $password); // Report if the connection fails or is successful. if (!$conn) { exit('<p>Your connection has failed.<p>' . mysqli_connect_error()); } echo '<p>You have connected successfully.</p>'; ?> </body> </html>

3. Go to http://example.com/test.php in a web browser. Remember to substitute example.com with your site’s domain or Linode’s IP address. The page should report that You have connected successfully. If you see an error message or if the page does not load, re-check your configuration.

4. Remove the test file once you have verified that the stack is working correctly:

   sudo rm /var/www/example.com/test.php