Install Php 8.1 Centos 7

PHP 8.1 is a significant update to the PHP language, introducing new features, performance improvements, and security enhancements. For developers running applications on CentOS 7, upgrading to PHP 8.1 can provide a competitive edge in terms of speed, efficiency, and modern coding capabilities. This guide will walk you through the steps required to install PHP 8.1 on a CentOS 7 system.

Prerequisites for Installing PHP 8.1 on CentOS 7

Before proceeding with the installation, ensure that your system meets the following requirements:

A CentOS 7 server
Root or sudo privileges
Access to a terminal or SSH client
Basic knowledge of Linux commands
An active internet connection

Step-by-Step Guide to Installing PHP 8.1 on CentOS 7

Step 1: Update Your System

Begin by updating your CentOS 7 system to ensure all existing packages are up to date. Run the following command:

yum update -y

Step 2: Enable Remi Repository

The Remi repository is a third-party repository that provides newer versions of PHP for CentOS systems. To enable it, execute the following commands:

yum install -y https://rpms.remirepo.net/enterprise/remi-release-7.rpm
yum install -y epel-release yum-utils

Step 3: Disable Default PHP Repositories

To avoid conflicts with the default repositories, disable them using the yum-config-manager tool:

yum-config-manager --disable remi-php54
yum-config-manager --disable remi-php55
yum-config-manager --disable remi-php56
yum-config-manager --disable remi-php70
yum-config-manager --disable remi-php71
yum-config-manager --disable remi-php72
yum-config-manager --disable remi-php73
yum-config-manager --disable remi-php74

Step 4: Enable PHP 8.1 Repository

Now, enable the repository for PHP 8.1:

yum-config-manager --enable remi-php81

Step 5: Install PHP 8.1

With the repository enabled, you can now install PHP 8.1 along with some common extensions:

yum install -y php81 php81-php-cli php81-php-fpm php81-php-mysqlnd php81-php-zip php81-php-devel php81-php-gd php81-php-mbstring php81-php-curl php81-php-xml php81-php-pear php81-php-bcmath php81-php-json

Step 6: Verify PHP Installation

After the installation is complete, verify that PHP 8.1 has been installed successfully by checking its version:

php -v

You should see output similar to:

PHP 8.1.x (cli) (built: date) ( NTS )

Configuring PHP 8.1 on CentOS 7

Setting Up PHP-FPM

For web applications, setting up PHP-FPM (FastCGI Process Manager) is crucial for handling heavy loads efficiently. Configure PHP-FPM by editing its configuration file:

nano /etc/opt/remi/php81/php-fpm.d/www.conf

Make necessary changes such as user, group, and listen directives, then save and exit the editor.

Enabling and Starting PHP-FPM Service

Enable and start the PHP-FPM service so that it runs on boot:

systemctl enable php81-php-fpm
systemctl start php81-php-fpm

Testing PHP Processing

To test if PHP is correctly processing files, create a test PHP file in your web server’s root directory:

echo "" > /var/www/html/phpinfo.php

Then, access this file from your web browser by navigating to http://your_server_ip/phpinfo.php. You should see the PHP information page.

Troubleshooting Common Issues During Installation

Dealing with Missing Dependencies

If you encounter errors related to missing dependencies during installation, use the following command to resolve them:

yum deplist php81 | awk '/provider:/ {print $2}' | sort -u | xargs yum -y install

Handling Conflicts with Existing PHP Versions

In case of conflicts with previously installed PHP versions, remove them before installing PHP 8.1:

yum remove php*

Be cautious as this will remove all existing PHP packages and could affect running applications.

Integrating PHP 8.1 with Web Servers

Integration with Apache

For Apache integration, install the mod_php module and restart Apache:

yum install -y php81-php
systemctl restart httpd

Integration with Nginx

Nginx requires setting up a PHP-FPM pool and configuring server blocks to use PHP-FPM. Refer to the PHP-FPM and Nginx documentation for detailed instructions.

Optimizing PHP 8.1 Performance

Opcode Caching

Install and configure OpCache for better performance:

yum install -y php81-php-opcache
nano /etc/opt/remi/php81/php.d/10-opcache.ini

Adjust settings like memory_consumption and max_accelerated_files as needed.

Realpath Cache Size

Increase the realpath_cache_size in your php.ini file to improve performance:

nano /etc/opt/remi/php81/php.ini

Find and set the directive:

realpath_cache_size = 4096k

Frequently Asked Questions

Can I run multiple PHP versions on CentOS 7?

Yes, you can use Software Collections (SCL) or run different versions of PHP-FPM on separate ports to run multiple PHP versions concurrently.

Is it safe to upgrade to PHP 8.1 on a production server?

Upgrading to PHP 8.1 should be done cautiously, ideally first in a staging environment. Ensure compatibility with your applications before upgrading production servers.

How do I switch between PHP versions?

You can switch between installed PHP versions using the scl command if you have installed PHP via Software Collections. Otherwise, you may need to adjust your web server configurations to point to the desired PHP-FPM version.

What are the key features of PHP 8.1?

PHP 8.1 introduces enums, readonly properties, fibers, intersection types, and performance improvements among other features.

Do I need to compile PHP 8.1 from source?

No, this guide uses the Remi repository, which provides precompiled PHP binaries for easy installation.