
PHP, an acronym for Hypertext Preprocessor, is an open-source scripting language used in web development. PHP runs on the server-side and is the powerhouse behind many popular web-based solutions such as WordPress and Moodle.
On Ubuntu 20.04, PHP 7.4 is the version available in the default package repository at the time of this post. However, PHP 8.0 is the latest version of the PHP language.
In this tutorial, our focus will be on the installation of PHP 7.4 for Apache and NGINX web servers running on Ubuntu 20.04.
Prerequisites
- An Apache or NGINX web server running on Ubuntu 20.04
- A user with sudo privilege
Install PHP 7.4 for Apache
Begin by checking for package updates with the command below.
$ sudo apt update
Next, install PHP 7.4 with the command below.
$ sudo apt install php7.4 -y
Once installed, run the next command to confirm the version of PHP.
$ php -v

Test PHP 7.4 on Apache
To test the PHP 7.4 installation on Apache, run the command below to create an index.php file in the default document root.
$ sudo nano /var/www/html/index.php
Next, copy and paste the sample PHP code below.
<?php
phpinfo();
?>
Save your changes and close the index.php file.
Now, open a web browser and enter serverIP/index.php.
Note: serverIP should be your actual server IP. For example, 192.168.1.100/index.php
You should see the PHP 7.4 info page which confirms that PHP is working properly.

Install PHP 7.4 for NGINX
Out of the box, NGINX does not have the capability to process PHP documents. Therefore, it is necessary to install and configure the PHP FastCGI Process Manager, i.e., PHP-FPM.
Firstly, check for package updates if you have not done so already.
$ sudo apt update
Next, install PHP-FPM 7.4 on Ubuntu 20.04 with the command below.
$ sudo apt install php7.4-fpm
After that, open the default NGINX server block file with:
$ sudo nano /etc/nginx/sites-available/default
In that file, locate the line that begins with index, and then add index.php to the list.

Next, locate the section titled # pass PHP scripts to FastCGI server and ensure that it looks like what you see in the code block below. Basically, specific lines have been uncommented.
# pass PHP scripts to FastCGI server
#
location ~ \.php$ {
include snippets/fastcgi-php.conf;
#
# # With php-fpm (or other unix sockets):
fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
# # With php-cgi (or other tcp sockets):
# fastcgi_pass 127.0.0.1:9000;
}
Save changes and close the server block file.
Test PHP 7.4 on NGINX
To test PHP 7.4 on NGINX, create an index.php file in the default document root as follows.
$ sudo nano /var/www/html/index.php
Now, copy and paste the sample PHP code below into the text editor.
<?php
phpinfo();
?>
Save and close the index.php file. Open a web browser and go to serverIP/index.php. For example 192.168.1.100/index.php
You should see the PHP 7.4 info page.

Conclusion
Following this tutorial, you should be able to install and configure PHP 7.4 on Apache and NGINX web servers. Questions and comments are highly welcomed.