If you’re seeing a decline in traffic or user counts in your Mapp Intelligence reports, there could be many reasons. One increasingly common cause is that your custom tracking domain is being blocked by ad and tracking blockers.
Many tracking setups use CNAME redirects to make tracking requests appear to originate from a first-party domain. However, modern ad blockers are now capable of detecting such redirects and are increasingly adding those domains to blacklists. As a result, some tracking data may never reach Mapp Intelligence.
This article explains the background and shows you how switching to a more resilient setup can help you maintain full data quality.
Why are CNAME-based tracking domains at risk?
When a custom tracking domain uses a CNAME redirect, it points to a Mapp domain. While this may appear as a first-party request to browsers, ad blockers can resolve these DNS entries and detect the underlying tracking infrastructure. When detected, the domain is often blacklisted — leading to blocked requests and lost tracking data.
What are the consequences?
Up to 15% of traffic may be lost due to blocked requests
Reports and analyses become incomplete
Personalization and segmentation become less reliable
KPIs may no longer reflect actual user behavior
What’s the recommended solution?
We recommend switching from a CNAME-based custom tracking domain to one that uses an A-Record. With this setup, your subdomain points directly to a Mapp server via its IP address, without redirecting via a Mapp domain. This makes detection by ad blockers significantly more difficult.
What needs to be considered during the switch?
Define a new subdomain
This subdomain will serve as your new custom tracking domain.
Configure the A-Record
The A-Record points directly to a Mapp IP address. Your contact at Mapp will provide the correct configuration.
Provide or request an SSL certificate
You can either provide your own certificate or request one from Mapp.
Check your cookie configuration
If tracking cookies were previously set via the old domain, they must be migrated to the new domain or reconfigured to be set via the main website domain.
⚠️ If cookies are not migrated properly, returning users may be treated as new users after the switch.
Update your tracking setup
The new domain must be added to your tag manager or directly into your tracking implementation. If Mapp can access your setup, we can make this change for you.
When is switching necessary?
If your current setup uses a CNAME redirect, we recommend making the switch even if you haven’t seen a noticeable drop in traffic yet. By switching to an A-Record now, you can reduce the risk of future data loss and ensure the long-term reliability of your tracking setup.
Need help with switching your custom tracking domain?
Our service team is happy to support you, from technical assessment to full implementation. Together, we’ll help you protect your data and keep your setup up-to-date.
Please reach out to your Customer Success Manager or open a request via the support portal.