What is UltraStack?

In this article, we cover the basics of our proprietary UltraStack caching system used for NGINX-powered Shared Hosting, WordPress Hosting and WordPress VPS Hosting plans for top web hosting performance and ultimate scalability. UltraStack includes the following fine-tuned software to enhance any content management system (CMS) or PHP/HTML/CSS/Javascript based website:

What’s Included?

NGINX Proxy Caching

NGINX reverse proxy server uses PHP to cache web content into memory to prevent loading source code for every new visitor. This improves the performance for any PHP/HTML/CSS website, not just WordPress. Learn more about NGINX and our cPanel Cache Manager.

Redis Object Caching

Redis, short for Remote Dictionary Server, provides object caching for SQL and other server processes within a database and your server RAM instead of using server hard drive resources. For more information, check out how to edit the Redis configuration file and configure Redis for WordPress.

Note: Redis Caching is not included on Shared and WordPress Hosting due to potential privacy issues between cPanel accounts.


PHP-FastCGI Process Manager (PHP-FPM) has many benefits over the outdated SuPHP which makes it more secure and efficient with improving website performance. PHP-FPM uses isolated “pools” of memory and processes per user with configurable max requests and timeout settings to minimize system resource usage. VPS and Dedicated server administrators may be familiar with PHP-FPM from the WebHost Manager (WHM) MultiPHP Manager or PHP-FPM service for Apache sections.

Brotli Compression

Brotli is a newer open-source compression algorithm which uses NGINX and less resources than the commonly used gzip. With better compression rates compared to gzip, Brotli can improve your website speed upon first visit – known as the time to first byte – within compatible browsers and content delivery networks (CDN) including Cloudflare and Sucuri.

Anything to Be Aware Of?

Our default caching configuration should improve most popular software. It will not cache a webpage during user engagement to negatively affect real-time changes. A popular example of this for e-commerce websites: customers adding products to the cart. The PHP opcode cache will speed up these updates regardless even if the individual page isn’t cached. Advanced users can modify such caching rules within cPanel Cache Manager.

Why NGINX over LiteSpeed?

Similar to why we chose PHP-FPM over SuPHP, many competitors use older caching software such as APC and LiteSpeed. NGINX, and its open source license, nurtures our dedication to improving user experience and security. We’ve gained years of experience working with NGINX on our managed VPS Hosting and scaled-down NGINX-powered WordPress Hosting plans for smaller initiatives.

Still have questions about how UltraStack can help you? Learn more about how UltraStack is configured. Or learn how to serve faster websites with our WordPress UltraStack VPS.

Jacqueem Content Writer I

Technical writer focused on cybersecurity and musicianship.

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  • I awoke on 7/1/20 to a VPS server with the UltraStack installed and a failed NGINX service. It appears that at 10PM on 6/30/20, my server ran a scheduled YUM UPDATE. On 7/1/20 at 5AM, my server ran another scheduled task that caused a reboot of services. NGINX failed to start.

    I have read that cPanel released an update about this same time. Can IMH support point me in the direction to resolve this.

    My /etc/nginx/error.log shows 2 different errors: nginx: [emerg] unknown “no_cache” variable
    [emerg] 6036#0: unknown directive “brotli_static” in /etc/nginx/vhosts/…

    Thank you,

    • Hello and thanks for contacting us. Unfortunately, you’ll need to contact Live Support for further assistance.

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