Introduction
The GridPane Nginx Stack also features Redis page and static asset caching as a high-speed and reliable in-memory solution.
Most people know and use Redis as a highly efficient, powerfully configurable, and incredibly fast object cache for things such as Database queries, but it can also serve double duty as a static caching solution integrated with Nginx.
Redis Nginx Page Caching: Best Use Cases
GridPane comes with 2 Nginx caching systems. The other is FastCGI, which employs microcaching.
Redis Nginx Page Caching is what we recommend for most websites.
If you’re not experiencing thousands of concurrent visitors hitting your website at the same time, and your content is fairly static, Redis Nginx Page Caching is usually the best option.
Redis is extremely performant at high levels of concurrent visitors, and it will also auto-purge itself more effectively than FastCGI, which can sometimes use a significant amount of RAM on very large websites.
There are, however, situations where FastCGI may be the better fit.
The Case for FastCGI
FastCGI Caching is perfect for websites with high concurrent traffic (where it has an edge over Redis Nginx Page caching), and it’s also ideal for websites where content regularly changes. For example, popular blogs and news websites that regularly publish new content and/or have active comments, or forums with publicly accessible content.
In these cases, microcaching is ideal, as it updates the cache in the background whenever a visitor loads a page, ensuring that all future visitors receive the latest content.
About GridPane’s Redis Cache Implementation
Nginx cache purging is one of the premium features of the Nginx Plus platform, but, as is usual with the open-source community, a resourceful community member has stepped into the gap and provided an invaluable asset to enable cache purging on the FOSS version of Nginx.
The GridPane stack is custom-compiled with the redis-nginx, redis2-nginx, and srcache-nginx-module, which allow a Redis server to be used as a static cache and enable cache purging when content updates.
2025 Update
GridPane now uses our own GridPane Nginx Helper plugin, which includes the functionality for FastCGI cache purging that was previously added in as a separate must-use plugin. This is a forked version of the Nginx Helper plugin by rtCamp, now that our goals for the plugin are different. We'll continue to contribute to Nginx Helper and also bring new features into our fork in the future.
1. Enable Nginx Redis Page Caching
You can enable Redis Nginx Page caching and change the cache TTL inside your website’s customizer.
Enabling Redis Nginx Page Caching
To get started, head over to the Sites page inside your account and click on the website you want to activate caching for to open the Site Customizer:
Click through to the Caching Tab, and then click Redis Caching Toggle:
Your site will now have Nginx Redis Caching enabled with GridPane custom configurations.
Adjust Cache Time To Live (TTL)
Time to live (TTL) is the amount of time your page is stored in a caching system before it’s deleted or refreshed.
The default setting for Redis Nginx Page caching is 30 days (2592000 seconds).
In most cases, 30 days is a good duration for your cache. However, if you need to change it, you can adjust the TTL inside the Page Cache TTL (seconds) box, and then click Update:
An example use case for this may be that you have a form that requires WordPress nonce validation.
Confirm Your Caching is Active
If you want to confirm your caching is now active, you can visit your site and check the response headers using the site inspector. You will see that caching has been enabled.
Part 3 of this article below covers this in more detail.
2. Configure the Nginx Helper Plugin
By default, we auto-configure the plugin with the correct caching type (Redis page caching in this case), and we exclude some common pages that should never be cached (learn more here).
Auto-Configuration
If you navigate to the plugin settings within your site dashboard (Dashboard > Settings > Nginx Helper), you’ll see we’ve preconfigured the Purging Options, Caching Method, and Redis Settings so that the plugin works correctly with Redis page caching.
The Caching Method and Redis Settings are set in the wp-config.php file, so they can’t be accidentally misconfigured.
Additional Configuration: Purging Conditions
Under Purging Conditions, you can select what content you would like to trigger the purging and updating of cache.
The default settings are suitable for almost all websites, and the Purge On Update setting is popular for websites using page builders who update the stylesheets on plugin updates.
Click Save All Changes when you have configured the options to suit your needs and now the cache will automatically purge outdated content as you update your GridPane site content.
Debug
The plugin also includes an option for debug, but it is highly unlikely that you will ever need to to use it.
To enable logging, you’ll need to edit your website’s wp-config.php file and add the following line:
define('NGINX_HELPER_LOG', true);Learn more about editing the wp-config.php file via the user-configs.php file on your GridPane servers here.
Once you’ve made your edit, you’ll see an additional box with further info, including the log location. Once you’ve completed your debug, be sure to remove the constant from your wp-config.php / user-configs.php file.
Important
If you switch from FastCGI to Redis Page caching or vice versa, make sure you also switch the caching method inside Nginx Helper plugin inside your website.
3. How to Check Caching Headers
First, open up your website in an incognito window. Next, right-click and choose “Inspect“, select the “Network” tab, and then reload the page. The result will look similar to the image below.
Click on your URL on the left-hand side to open up the box on the right, then down until you see the “Response Headers” section. If our caching is active you’ll see the following for Redis Nginx Caching:
X-Grid-SRCache-Fetch
If caching is turned on, you’ll see X-Grid-SRCache-Fetch with a value of either:
HIT | MISS | BYPASS
HIT means the website is cached.
MISS means this page hadn’t been cached yet, as it’s the first time it’s been visited since either the cache has been activated or cleared -on reload, it should say HIT.
BYPASS means this page has been excluded and will never be cached.
Here is what Redis Nginx Page caching looks like when turned on (on activating, I got a value of MISS, but now the page has loaded, on reload, I have a value of HIT as shown below):
In the above image, you can also see X-Grid-SRCache-TTL: 2592000.
TTL stands for time to live, and this tells your browser how long it should cache this page for. The number next to it is the time in seconds. 2592000 converted into days = 30. This is the default value for Redis Page caching, and X-Grid-SRCache-TTL: 2592000 tells your browser to cache this page for 30 days.
Caching won’t take place while you are logged in
When logged into your website you will see that the cache is bypassed, and in your dashboard you will see:
cache-control: private, no-store
This forces browsers and CDNs to never cache.
Update/Reinstall the GridPane Caching Plugin
If you’ve deleted the GridPane caching plugin, the easiest way to reinstall it and ensure it’s properly configured is to simply toggle it to OFF within your account dashboard, and then toggle it back ON.
If you need to download the plugin for your Git repository, you can find it in our Git repo here:
The plugin will automatically be updated when we release new updates.
Further Reading
You may also interested in the following caching articles: