Imagine driving on a highway with zero traffic, smooth, fast, and efficient. Now, imagine your WordPress website running just as fast. That’s exactly what Redis Object Cache can do for your WordPress site. It stores frequently used data in memory, so your website doesn’t have to repeatedly fetch the same data from the database again. The result? Lightning-fast page loads and happy visitors.

In this guide, I’ll walk you through the process of installing the Redis Object Cache plugin into WordPress, no technical hassles, just a clear, step-by-step guide that anyone can follow.

What is Redis, and why use Redis with WordPress?

Redis (Remote Dictionary Server) is a powerful tool that acts like a super-fast memory storage for your website. It temporarily saves frequently accessed data like settings, posts, and user sessions, so WordPress doesn’t have to fetch it from the slower MySQL database every time.

Think of it like your browser’s autocomplete, saving you from typing the same thing again and again. Redis does that for your website!

How Does Object Caching Work?

Every time someone visits your WordPress site, WordPress runs several database queries. This can slow down things, especially when you have many visitors.

With Object Caching, those repeated queries are stored in memory (RAM). When the same data is needed again, it’s pulled from Redis instead of the database, much faster!

Benefits of Using Redis Object Cache

• Faster Page Loads: Speed improves user experience and SEO.
• Reduced Server Load: Fewer database hits mean more efficient resource use.
• Scalability: Perfect for busy websites or e-commerce stores.
• Improved User Experience: Faster loading times and happier visitors.

Prerequisites Before You Start

Before starting the installation, make sure you have:

• A VPS or dedicated server 
• Root or sudo access for installing packages on server
• PHP version 7.2 or higher
• A WordPress site

Step-by-Step Guide:

Step:1 Install Redis on Your Server

If Redis isn’t already installed, here’s how to do it on Ubuntu:

sudo apt update
sudo apt install redis-server -y

sudo apt update
sudo apt install redis-server -y

Enable it to start automatically:

sudo systemctl start redis

sudo systemctl start redis

To check if Redis is running:

redis-cli 

redis-cli 

After that, enter the below command;

ping

ping

If it replies with “PONG,” you’re good to go!

Check out our detailed guide on step-by-step Redis Installation: https://serveravatar.com/install-redis-cache-ubuntu/

Step 2: Enable Redis PHP Extension

Redis needs a PHP extension to work with WordPress. Let’s install the PHP Redis extension. I’m installing here for PHP 8.1, adjust it based on your version:

sudo apt install php-redis

sudo apt install php-redis

Then restart web server. Use the below command to restart apache web server:

sudo systemctl restart apache2

sudo systemctl restart apache2

Or, if you’re using Nginx:

sudo systemctl restart nginx

sudo systemctl restart nginx

If you’re using ServerAvatar, this process is even easier. 

• Just navigate to the Server panel in ServerAvatar, and navigate to the Services section from the left-hand sidebar.
• Click on the “restart” icon as shown in the image below.

Step 3: Install Redis Object Cache Plugin

Now it’s time to install redis object cache for your WordPress application.

• Go to your WordPress dashboard.
• Navigate to Plugins > Add New.

• Search for Redis Object Cache.
• Click Install Now button. Once installed, click on the Activate button to activate the plugin.

That’s it! You’ve installed the plugin.

Step 4: Configure the Plugin Settings

Once the plugin is activated, go to the Plugins >> Installed Plugins, and click on the “Settings” for Redis Object Cache Plugin.

• You’ll see a button that says Enable Object Cache. Just click on it.

Now, the plugin will connect to your Redis server and start caching immediately.

Note: If your Redis Password is not defined in your wp-config file, you will not be able to enable the Object Cache, and you will see the error message that Redis is unreachable, as you can see in the below image.

Add the Redis Password to your application’s wp-config file to resolve this issue. If you are using ServerAvatar to manage your servers and applications, it is very easy to add the Redis password. Just follow the steps below: 

• Navigate to the application panel by clicking on the dashboard icon next to your WordPress application.

Click on the “File Manager” from the left-hand sidebar. Go to the “public_html” directory and open the “wp-config.php” file.

• Add your redis password in config file: define('WP_REDIS_PASSWORD', 'YOUR_REDIS_PASSWORD');
• Enter your redis password at the place of YOUR_REDIS_PASSWORD; Click on the “Save Changes” button after adding.

That’s it! Now, try to enable Object Cache.

Step 5: Test the Redis Connection

You should see a green message at “Status” that says: “Connected”, Redis is active, and object cache is enabled.

If you see this, Congratulations!, you’re now officially using Redis!

How to Know If Redis Is Working Properly

You can verify Redis usage with this command on your server:

redis-cli

redis-cli

Then type the below command and enter your Redis password at the place of “REDIS_PASSWORD” to authenticate.

AUTH REDIS_PASSWORD

AUTH REDIS_PASSWORD

Then write “monitor” to see the entries.

monitor

monitor

As you can see in the following image: 

Then browse your website in another tab. You’ll see live entries popping up, which means Redis is actively caching data.

Common Issues and How to Fix Them

Issue 1: Plugin Can’t Connect to Redis

• Make sure that Redis is running by using the command “sudo systemctl status redis”
• Check that the PHP extension is installed and active.

Issue 2: White Screen After Activation

• Disable the plugin. You can use FTP or File Manager to do that.
• Check PHP error logs for clues.

Issue 3: Redis Stops Working After Server Reboot

• Make sure that Redis is enabled, or you can use the command “sudo systemctl enable redis” to enable redis.

How to Clear Redis Cache in WordPress

Sometimes, you might need to manually clear the cache:

• Go to the Settings tab in your WordPress admin dashboard and then to Redis
• Click on the Flush Cache

You can also run this command from your server:

redis-cli flushall

redis-cli flushall

Use this command with caution, as this removes all cached data.

Alternatives to Redis Object Cache

Not a fan of Redis? Here are a few other options:

• Memcached: It is a memory-based cache solution.
• W3 Total Cache: It includes object caching and more.
• LiteSpeed Cache: Great if you’re using a LiteSpeed server.

Each tool has its pros and cons, but Redis remains a top performer for object caching.

Conclusion

If you want your WordPress website to run faster and handle more traffic, Redis Object Cache is a no-brainer. It’s lightweight, powerful, and surprisingly easy to set up.

Throughout this guide, you’ve seen how easy it is to get Redis up and running, from installing it on your server to enabling it through a simple WordPress plugin. With just a few steps, you can significantly cut down page load times, reduce server strain, and create a faster, more reliable experience for your visitors.

Whether you’re managing a high-traffic blog, a growing WooCommerce store, or a content-heavy business site, Redis Object Cache helps your site handle more users with less stress on your infrastructure. It’s scalable, efficient, and works seamlessly alongside other performance tools like CDNs.

And if you’re using ServerAvatar, the entire process becomes even simpler with an intuitive interface and built-in support for Redis management, making it accessible even for users without deep technical knowledge.

Don’t be intimidated by the technical stuff; once Redis is set up and running, you’ll barely have to touch it again. Your website visitors will enjoy faster pages, and you’ll enjoy fewer headaches.

Frequently Asked Questions (FAQs)