Installing and Configuring PHP on Ubuntu

PHP (Hypertext Preprocessor) is a widely-used open-source programming language specifically designed for web development. Created by Rasmus Lerdorf in 1993, PHP originally stood for "Personal Home Page" but is now a recursive acronym for "PHP: Hypertext Preprocessor". PHP allows embedding server-side code into HTML, simplifying the creation of dynamic web pages that interact with users and databases. According to W3Techs data from July 2025, PHP is used on approximately 77% of all websites with a known server-side programming language. The current stable version is PHP 8.4.10, released on July 3, 2025.

PHP is popular due to its beginner-friendly simplicity and powerful capabilities for professional developers. It powers popular content management systems (CMS) like WordPress, Drupal, and Joomla, and is used on major platforms such as Wikipedia and Etsy.

Why Use PHP with a Web Server?

PHP plays a key role in web development thanks to the following capabilities:

• Dynamic content generation: PHP enables creating web pages whose content changes based on user input, time, database data, or other factors. For example, PHP can generate personalized pages like user profiles or search results.
• Database integration: PHP supports working with various databases including MySQL, PostgreSQL, SQLite and others. This makes it ideal for applications requiring data storage and processing, such as e-commerce stores or blogs.

These capabilities make PHP the foundation for dynamic web applications, providing the flexibility and functionality required for modern websites.

Prerequisites

Before installing PHP, ensure the following conditions are met:

• Installed Apache web server: PHP will integrate with Apache as described in the "Web Server Installation" article. To verify Apache installation, execute:
  apache2 -v

  If Apache is not installed, follow the instructions from the mentioned article.

• Ubuntu operating system: This article assumes Ubuntu 24.04 (LTS) is used. Instructions can be adapted for other Ubuntu versions or Linux distributions.
• Administrator privileges: Root or sudo access is required for installing packages and modifying configuration files.
• Terminal access: Ensure you have terminal access locally or via SSH for remote servers.

It's also recommended to update the system before installation to avoid dependency issues.

Installing PHP on Ubuntu

PHP installation on Ubuntu is performed using the apt package manager. Follow these steps:

1. Update package lists
   To ensure you're installing the latest software versions, update the package index:
   sudo apt update
2. Install PHP and Apache module
   Install PHP and the integration module for Apache:
   sudo apt install php libapache2-mod-php

   This command will install the latest PHP version available in Ubuntu repositories (typically PHP 8.3 for Ubuntu 24.04) and the libapache2-mod-php module which enables Apache to process PHP scripts.

3. Check installed PHP version
   After installation, verify the PHP version to confirm successful installation:
   php -v

   The output should display the version, for example:

   PHP 8.3.0 (cli) (built: Dec 10 2023 12:34:56) ( NTS )
4. Install additional extensions
   For typical web development tasks, install the following extensions:
   sudo apt install php-mysql php-gd php-curl
   • php-mysql: Enables PHP to interact with MySQL databases, essential for applications like WordPress.
   • php-gd: Provides image processing functions, such as creating thumbnails or watermarks.
   • php-curl: Used for making HTTP requests, for example when integrating with APIs.

   If using a different PHP version, package names may include the version (e.g., php8.3-mysql). For standard installations, the specified package names will work as they match the default PHP version.

Configuring PHP

After installing PHP, configure its parameters to meet your application requirements. The main PHP configuration file for Apache is located at /etc/php/<version>/apache2/php.ini, where <version> is your installed PHP version (e.g., 8.3).

1. Locate the configuration file
   For PHP 8.3, the file is at:
   /etc/php/8.3/apache2/php.ini

   To confirm the path, execute:

   php --ini

   This will show the location of php.ini for both Apache and CLI (command line).

2. Open the file for editing
   Use a text editor like nano to edit the file:
   sudo nano /etc/php/8.3/apache2/php.ini
3. Modify key parameters
   Find and modify the following parameters according to your needs:
   • memory_limit: Defines the maximum memory a PHP script can use. Default is often 128M. For more demanding applications, increase to:
     memory_limit = 256M
   • upload_max_filesize: Sets maximum upload file size. Default is 2M. For larger files, increase to:
     upload_max_filesize = 10M
   • post_max_size: Defines maximum POST data size. Must be greater than or equal to upload_max_filesize. For example:
     post_max_size = 12M
4. Save changes and restart Apache
   After making changes, save the file (in nano press Ctrl+O, then Enter, and Ctrl+X to exit) and restart Apache to apply settings:
   sudo systemctl restart apache2

Integrating PHP with Apache

The libapache2-mod-php module automatically integrates PHP with Apache during installation. However, you can verify if the module is activated and enable it manually if needed.

1. Check PHP module activation
   Execute:
   sudo a2enmod php8.3

   Replace 8.3 with your PHP version if different. If the module is already enabled, you'll see an activation message.

2. Restart Apache
   Apply changes by restarting Apache:
   sudo systemctl restart apache2
3. Check Apache status
   Verify Apache is functioning correctly:
   sudo systemctl status apache2

   The output should show active (running) status.

Testing PHP Installation

To verify PHP is properly installed and integrated with Apache, create a test page:

1. Create info.php file
   Create a file in the web server directory /var/www/html/:
   echo "" | sudo tee /var/www/html/info.php

   The phpinfo() function outputs detailed PHP configuration information including version, modules, and settings.

2. Check the page in browser
   Open a browser and navigate to http://localhost/info.php or http://<server_IP>/info.php. You should see a PHP information page showing version, installed modules, and configuration parameters.
3. Security
   After testing, delete the info.php file as it may reveal sensitive server information:
   sudo rm /var/www/html/info.php

   If you wish to keep the file, restrict access by modifying permissions:

   sudo chmod 600 /var/www/html/info.php

Useful Configuration Tips

For optimizing PHP performance, configure additional parameters in php.ini:

• Error reporting settings
  For development, enable full error display to simplify debugging. Locate in php.ini:
  error_reporting = E_ALL
  display_errors = On

  In production environments, disable error display for security:

  display_errors = Off

  Errors will instead be logged to a file (e.g., /var/log/php_errors.log if configured).

• Setting timezone
  Configure the date.timezone parameter for correct date/time function operation:
  date.timezone = Europe/Moscow

  Supported timezones are listed in PHP documentation.

• Additional parameters
  Consider configuring these parameters:
  • max_execution_time: Maximum script execution time in seconds. Default is 30 seconds. For long operations, increase to:
    max_execution_time = 60
  • session.gc_maxlifetime: Session lifetime in seconds. Default is 1440 (24 minutes). For longer sessions:
    session.gc_maxlifetime = 3600

Troubleshooting Common Issues

If PHP isn't functioning as expected, follow these steps:

1. Check Apache status
   Verify Apache is running:
   sudo systemctl status apache2

   If the service isn't active, restart it:

   sudo systemctl restart apache2
2. Review error logs
   PHP error logs are typically written to the file specified in php.ini (error_log parameter). Also check Apache logs:
   sudo cat /var/log/apache2/error.log
3. Common issues
   • info.php page not displaying: Ensure the PHP module is activated (sudo a2enmod php8.3) and Apache is restarted.
   • Dependency errors: If installation failed, repair dependencies:
     sudo apt-get install -f
   • Permission issues: Verify files in /var/www/html/ are accessible to Apache:
     sudo chown -R www-data:www-data /var/www/html
     sudo chmod -R 755 /var/www/html

Installing and configuring PHP on Ubuntu is a straightforward process that prepares your server for dynamic web applications. By following these steps, you can install PHP, integrate it with Apache, configure key parameters, and test the setup. PHP remains an essential tool for web development thanks to its popularity, community support, and compatibility with popular CMS platforms like WordPress.

Table: Key php.ini Parameters