How to Install PHP 8.1 in Rocky Linux 9

Adding Required Repositories

To install PHP 8.1 on Rocky Linux 9, you need to add the EPEL (Extra Packages for Enterprise Linux) and REMI repositories. These repositories provide extra packages and updates not found in the default Rocky Linux repositories.

EPEL Repository

Install the EPEL repository:

sudo dnf install epel-release

Benefits of EPEL:

• Access to more software packages
• Regular updates and security patches
• Community-maintained repository with good packages

dnf repolist | grep epel

REMI Repository

Install the REMI repository:

sudo dnf install http://rpms.remirepo.net/enterprise/remi-release-9.rpm

Installing DNF Utilities

DNF utilities offer extra functions for managing packages and repositories. To install the dnf-utils package, run:

sudo dnf install dnf-utils

Enabling PHP 8.1 Remi Repository

To enable the PHP 8.1 Remi repository on Rocky Linux 9:

1. Reset the PHP module:

   sudo dnf module reset php

2. Install PHP 8.1 module:

   sudo dnf module install php:remi-8.1

Installing PHP 8.1 and Extensions

Install PHP 8.1 and common extensions:

sudo dnf install php php-cli php-fpm php-mysqlnd php-zip php-devel php-gd php-mcrypt php-mbstring php-curl php-xml php-pear php-bcmath php-json

Popular PHP 8.1 extensions and their uses

Configuring PHP-FPM

1. Start PHP-FPM service:

   sudo systemctl start php-fpm

2. Enable PHP-FPM to start on boot:

   sudo systemctl enable php-fpm

PHP-FPM configuration tips

• Adjust pm.max_children based on server resources
• Set proper memory_limit in php.ini
• Configure upload_max_filesize for file uploads

Optimizing PHP 8.1 for Production

Performance tuning

• Enable OPcache
• Adjust memory_limit and max_execution_time
• Configure PHP-FPM process manager

Security considerations

• Disable expose_php in php.ini
• Set correct file permissions
• Keep PHP and extensions updated

Core Installation

To install PHP 8.1 on your Rocky Linux 9 web server, run this command:

sudo dnf install php

This command installs the main PHP 8.1 package and its dependencies.

sudo dnf module list php

sudo dnf install epel-release
sudo dnf install https://rpms.remirepo.net/enterprise/remi-release-9.rpm
sudo dnf module enable php:remi-8.1

Verifying the Installation

After installation, check the PHP version:

php -v

You should see output like:

PHP 8.1.x (cli) (built: ...) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.1.x, Copyright (c) Zend Technologies

PHP Configuration

The main PHP config file is at /etc/php.ini. Here are some settings you might want to change:

Memory Limit

memory_limit = 256M

Maximum Upload File Size

upload_max_filesize = 20M
post_max_size = 20M

Error Reporting

error_reporting = E_ALL
display_errors = Off
log_errors = On
error_log = /var/log/php_errors.log

PHP-FPM Configuration

If you're using PHP-FPM (FastCGI Process Manager), you can install it with:

sudo dnf install php-fpm

Start and enable PHP-FPM:

sudo systemctl start php-fpm
sudo systemctl enable php-fpm

Creating a PHP Info File

To test your PHP installation, create a PHP info file:

1. Go to the web root directory:

   cd /var/www/html

2. Create and edit the info.php file:

   sudo nano info.php

3. Add the phpinfo() function to the file:

   <?php
   phpinfo();
   ?>

4. Save the file and exit the editor (in nano, press Ctrl+X, then Y, then Enter).

sudo cp /var/www/html/info.php /var/www/html/info.php.bak

Accessing the PHP Info Page

To view your PHP configuration through a web browser:

1. Open a web browser on your local machine.

2. Enter this URL, replacing your_server_ip with your server's IP address or domain name:

   http://your_server_ip/info.php

3. You should see a page showing details about your PHP installation.

Key Information Displayed

The PHP info page provides data about your setup:

• PHP version
• Loaded modules
• Server environment
• PHP settings

Examples

• Version Check: A developer needs to check if the server supports PHP 8.1 features like enums.
• Module Verification: A project needs the GD library for image processing.
• Environment Details: Troubleshooting session issues by checking the session save path.
• Configuration Review: Adjusting max_execution_time for a long-running script.

Security Precautions

After testing, remove the info.php file:

sudo rm /var/www/html/info.php

This step prevents unauthorized access to your server configuration details.

Restarting the Web Server

After installing PHP 8.1 and its modules, restart the Apache web server. This step applies the changes and makes PHP work correctly with Apache.

Restart Commands

Use one of these commands to restart the Apache web server:

Both commands restart Apache, but systemctl is more modern and offers more options.

Checking Apache Status

After restarting, check if Apache is running:

sudo systemctl status httpd

This command shows the status of the Apache service. Look for "active (running)" in the output.

Troubleshooting

If you see errors, check the Apache error log:

sudo tail -f /var/log/httpd/error_log

This command displays the last few lines of the error log and updates in real-time.

Common Issues and Solutions

• Permission Errors: Check file permissions for your web files.
• Module Conflicts: Check if new modules conflict with existing ones.
• Port Conflicts: Check if another service is using port 80 or 443.

Enabling Apache on Boot

To make Apache start when your server boots up, run:

sudo systemctl enable httpd

Testing PHP Installation

After restarting Apache, test your PHP 8.1 installation:

1. Create a test file:

   echo "<?php phpinfo(); ?>" | sudo tee /var/www/html/phpinfo.php

2. Access the file in your web browser: http://your_server_ip/phpinfo.php

3. Review the PHP configuration information displayed.

Next Steps

• Set up virtual hosts for your websites.
• Install PHP extensions for your projects.
• Configure PHP settings in php.ini for good performance.
• Set up a database server if needed (e.g., MySQL, PostgreSQL).

Your PHP 8.1 installation on Rocky Linux 9 is now ready. You can start developing PHP applications or install content management systems that use PHP.