The Ezoic platform automates multivariate testing by acting as a proxy, which is typically achieved by changing name servers at your registrar or installing the Cloudflare app if you are a Cloudflare customer.
When you add a site to the Ezoic system, either by creating a new account or adding a site to your existing Ezoic account, the current DNS records are imported and replicated in your Ezoic dashboard. These include all canonical values such as www, A records, and MX records for email.
If the site is marked as OFF in Ezoic, all requests are passed directly to your host. It is recommended to keep the Ezoic system off while setting up EzoicAds.
When the system is turned on, the dashboard settings you configure will direct a portion of the traffic to the testing setup and the rest to the original setup.
When a user visits the website, their browser calls for the content and is directed to the name servers for the site. Ezoic manages these requests and directs the user to the IP address of the HTML, either pulling in cached versions from a CDN or directly from your host. All requests are called back to your original server using the IP address of your host. Ezoic then sends the user to an experimental page (which includes EzoicAds ads) or serves the content normally.
In summary, the DNS settings at your registrar or Cloudflare are replicated in your Ezoic dashboard under Settings > DNS. Your website content IP does not change. All DNS records are replicated in Ezoic to ensure they adhere to the same rules for the site. Ezoic creates Cloudfront DNS settings in the Ezoic DNS to ensure that all Ezoic sites get CDN support (caching content either with Cloudflare or Amazon's Cloudfront). When the site is OFF in the system, all requests continue to go to the same IP.