Install LEMP on CentOS 7

LEMP is a combination of software that are used to serve dynamic web pages and web applications. LEMP is an acronym for:

• A Linux operating system
• Nginx (Engine X) webserver
• MySQL database
• PHP

In this guide, we’ll get a LEMP stack with PHP 7.4 installed on a CentOS 7 server, using MariaDB as the database management system. MariaDB works as a drop-in replacement for the original MySQL server, which in practice means you can switch to MariaDB without having to make any configuration or code changes in your application.

The backend will be stored in the MySQL database and the dynamic processing will be handled through PHP. In this tutorial, we will go through the steps on how to set it up on CentOS 7.

Note: The following steps will be exactly the same if you would want to set it up on CentOS 8.

Prerequisites

Before we go ahead with the tutorial, you will need to have the following:

1. A regular non-root user account with Sudo privileges
2. A basic understanding of bash programming commands
3. An CentOS 7 system (or CentOS 8)

Now that we already have acquired the needed things, let’s go ahead and start setting LEMP on your system.

Step 1: Install Nginx

We will be using the Nginx webserver to deliver and display web pages to our visitors. In order to get the latest version of Nginx, we will first install the EPEL repository.

sudo yum install epel-release

Once the EPEL repository is set up on your server, we can go ahead and install the Nginx package using the following command:

sudo yum install nginx

Don’t forget to press y to continue with the installation. Once Nginx is successfully installed, we will go ahead and start the service using the systemctl command.

sudo systemctl start nginx

sudo systemctl enable nginx

The second command (enable) will make Nginx start during boot up.

Now that we have the server up and running, you can run a quick test by entering the following URL on your favourite web browser.

http://server_domain_name_or_IP/

If you see the following on your display, then you have successfully installed the first layer of the LEMP stack: Nginx.

Step 2: Install MariaDB

MariaDB is an open-source database management system that is a backwards-compatible replacement for MySQL. It is a multi-threaded relational database management system. For the complete MariaDB installation with all the details, you can check our article using the link.

To install MariaDB, enter the following yum command:

sudo yum install mariadb-server mariadb

Don’t forget to press y when prompted to continue!

Once the installation is completed, enter the command below to start the service:

sudo systemctl start mariadb

MariaDB comes with a secure installation script that should be run to have the proper configurations. You can run the secure installation script by:

sudo mysql_secure_installation

During the setup, you will be prompted to

1. Change the root password
2. Remove anonymous users
3. Disallow root logins remotely
4. Remove test database and access to it
5. Reload privilege tables

Each step will be explained in detail and we recommend to answer with y to all questions mentioned.

Once the secure script is run, we will enable MariaDB to start up during bootup:

sudo systemctl enable mariadb.service

Step 3: Install PHP

PHP is the last part of the LAMP stack. PHP processes the code for showing dynamic content and once connected with the MySQL database, it will process and will be displayed through the Nginx webserver.

The PHP version available by default within CentOS 7 servers is outdated, and for that reason, we’ll need to install a third-party package repository in order to obtain PHP 7+. Therefore, we will use the Remi repository to install PHP 7.2.

sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

Now that we have the Remi repository added to our system, we will run the following command to enable the Remi package to get PHP 7.4 installed:

sudo yum-config-manager --enable remi-php74

We will also install the yum-utils package:

sudo yum install yum-utils

Now we can proceed to use the yum command for installing PHP and several most common PHP modules.

sudo yum install php-fpm php-opcache php-cli php-gd php-curl php-mysql

The installation will prompt you to continue, and when it does press y and proceed with the installation.

The default PHP FPM settings are to run as an apache user on port 9000 but we will change the user to Nginx and switch from TCP socket to Unix socket. It sounds a bit complicated, but all of this can be done within one configurations folder.

To make the following changes, we will use the nano text editor to open www.conf configurations file:

sudo nano /etc/php-fpm.d/www.conf

In the opened window, be sure to change the data according to the following below:

...
user = nginx
...
group = nginx
...
listen = /run/php-fpm/www.sock
...
listen.owner = nginx
listen.group = nginx

Save the file and exit the nano text editor.

Now we will provide the necessary permissions for the var/lib/php directory.

chown -R root:nginx /var/lib/php

Now as the final step, we will start the PHP service and enable it to work during boot up using the following commands.

sudo systemctl enable php-fpm

sudo systemctl start php-fpm

Step 4: Configuring Nginx to process PHP pages

We have all the needed components of the LEMP stack installed and set up on our CentOS 7 server. We will need to make a slight configuration to tell Nginx to use our PHP processor for dynamic content.  Nginx has a dedicated directory where we can define each hosted website as a separate configuration file, using a server block.

The default installation does not have any files in this directory, therefore, we will create a new file to serve as the default PHP website on this server.

sudo nano /etc/nginx/conf.d/default.conf

Copy the following PHP server definition block to your configuration file, and don’t forget to replace the server_name directive so that it points to your server’s domain name or IP address:

server {
    listen       80;
    server_name  server_domain_or_IP;
    root   /usr/share/nginx/html;
    index index.php index.html index.htm;
    location / {
        try_files $uri $uri/ =404;
    }
    error_page 404 /404.html;
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/html;
    }
    location ~ \.php$ {
        try_files $uri =404;
        fastcgi_pass unix:/var/run/php-fpm/php-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }
}

Save and close this file. Now restart the Nginx web server so that the changes will come into effect.

sudo systemctl restart nginx

By now your web server is set up perfectly, and the next step is to test the PHP integration.

Final Step: Test the PHP integration

Now that your web server is set up, we can create a test PHP script to make sure Nginx is correctly handling .php scripts with the help of php-fpm.

Using the nano command, we will create a test PHP page:

nano /usr/share/nginx/html/info.php

Now copy and paste the following content. It will show display the information about the current PHP environment running on the server.

<?php
phpinfo();

If you see a similar page as shown below, the PHP integration was successful.

Conclusion

Congratulations on successfully installing the LEMP stack on CentOS 7 server. We hope that you had a smooth installation process using the above-mentioned guidelines. Now you are ready to explore all the possibilities that the LEMP stack has to offer.

If you will come across any kind of problems, don’t hesitate to contact us through the comment section below!