How to Install Redis on AlmaLinux, RockyLinux, and CloudLinux Using WHM/cPanel

Redis is an open-source, in-memory data structure store that’s often used as a cache, message broker, and database to improve performance for dynamic web applications. This guide will show you how to install Redis on AlmaLinux 8 and 9, RockyLinux (latest versions), and CloudLinux 8 and 9 using WHM/cPanel.

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Table of Contents

1. Prerequisites
2. Installing Redis on AlmaLinux 8 and 9 with WHM/cPanel
3. Installing Redis on RockyLinux with WHM/cPanel
4. Installing Redis on CloudLinux 8 and 9 with WHM/cPanel
5. Installing the Redis PHP Extension
6. Verifying the Installation
7. Common Issues and Troubleshooting
8. Conclusion

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1. Prerequisites

Before starting the installation, make sure you have the following:

• WHM/cPanel installed and running.
• Root access to your server.
• PHP installed on your server.
• EasyApache 4 installed for managing PHP extensions.

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2. Installing Redis on AlmaLinux 8 and 9 with WHM/cPanel

AlmaLinux is a RHEL-based distribution that is fully compatible with WHM/cPanel.

Step 1: Log in to WHM

Go to https://your-server-ip:2087/ and log in using your root credentials.

Step 2: Install Redis

First, update your system and install Redis using the following commands:

sudo dnf update -y
sudo dnf install redis -y

Step 3: Start and Enable Redis

Enable Redis to start on boot and start the service:

sudo systemctl enable redis
sudo systemctl start redis

Step 4: Confirm Redis is Running

Check the status of Redis to make sure it’s running:

sudo systemctl status redis

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3. Installing Redis on RockyLinux with WHM/cPanel

The process for installing Redis on RockyLinux is similar to that on AlmaLinux.

Step 1: Log in to WHM

Access WHM by navigating to https://your-server-ip:2087/ and logging in with root access.

Step 2: Install Redis

Update your system and install Redis:

sudo dnf update -y
sudo dnf install redis -y

Step 3: Enable and Start Redis

Enable Redis to start at boot and start the service:

sudo systemctl enable redis
sudo systemctl start redis

Step 4: Verify Redis is Running

Check Redis’s status:

sudo systemctl status redis

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4. Installing Redis on CloudLinux 8 and 9 with WHM/cPanel

CloudLinux includes advanced features such as CageFS and ALT-PHP, which are important when installing Redis in shared hosting environments.

Step 1: Log in to WHM

Navigate to https://your-server-ip:2087/ and log in with root credentials.

Step 2: Install Redis

First, update your system and install Redis:

sudo yum update -y
sudo yum install redis -y

Step 3: Enable and Start Redis

Enable Redis to start on boot and start the service:

sudo systemctl enable redis
sudo systemctl start redis

Step 4: Install Redis for ALT-PHP

If you’re using ALT-PHP, you’ll need to install the Redis PHP extension for each version of PHP:

for version in  alt-php{70,71,72,73,74,80,81}; do
    yum install $version-pecl-redis -y
done

Step 5: Update CageFS

After installing Redis for ALT-PHP, update the CageFS skeleton:

cagefsctl --force-update

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5. Installing the Redis PHP Extension

To integrate Redis with your PHP environment, you need to install the Redis PHP extension via EasyApache 4.

Step 1: Open EasyApache 4 in WHM

In your WHM dashboard, search for EasyApache 4 in the search bar and open it.

Step 2: Customize Your PHP Installation

Click on Customize next to your profile. Under PHP Extensions, search for Redis.

Step 3: Install the Redis Extension

Select the PHP versions you are using and enable the Redis extension by checking the box.

Step 4: Provision and Restart Apache

Click Review and then Provision to apply the changes. Once complete, restart Apache:

sudo systemctl restart httpd

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6. Verifying the Installation

To verify that Redis is working with PHP, follow these steps:

Step 1: Create a PHP Info File

Create a PHP file to check if Redis is installed:

echo "<?php phpinfo();" | sudo tee /usr/local/apache/htdocs/info.php

Step 2: Open the PHP Info Page

Open your browser and navigate to http://your-server-ip/info.php. Look for Redis in the PHP information.

Step 3: Remove the PHP Info File

For security reasons, remove the info.php file once you’ve confirmed Redis is installed:

sudo rm /usr/local/apache/htdocs/info.php

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7. Common Issues and Troubleshooting

Issue 1: Redis Not Appearing in PHP Info

Solution:

• Ensure the Redis extension is enabled for the correct PHP version in EasyApache 4.
• Restart Apache after provisioning the Redis extension.

Issue 2: Redis Fails to Start

Solution:

• Use journalctl -xe to diagnose potential issues with Redis failing to start.
• Ensure the Redis port (default 6379) is available and not blocked by a firewall.

Issue 3: Redis Not Working with ALT-PHP

Solution:

• Install the Redis PHP extension for all ALT-PHP versions using the command in the CloudLinux section.
• Run cagefsctl --force-update to ensure new extensions are properly applied in CageFS.

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8. Conclusion

Installing Redis on AlmaLinux, RockyLinux, and CloudLinux using WHM/cPanel is straightforward. Redis is an essential tool for optimizing the performance of dynamic web applications by reducing database load and improving speed. EasyApache 4 makes it simple to set up Redis with PHP. Make sure to verify the installation and use the troubleshooting steps if any issues arise.

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