Visitor ID service - 3rd party fallback/demdex.net cookie not set?

[Løjmann]

Hi,

Analytics and Visitor ID Service is implemented using DTM. We uses AppMeasurement 1.5.1 and Visitor ID Service 1.5.2. The site uses custom tracking servers/CNAMES like stats.sitexyz and sstat.site.xyz, and we have set the Analytics Tracking Server fields as well as the Marketing Cloud Server fields to the same as the CNAME record.

However, not all browsers (who accepts 3rd party cookies) do get the demdex.net cookie set, why we won't have same visitor ID across different  domains. That is a major issue for us, as we need to do cross-domain analysis with data extracted via data feed or Data Warehouse.

Have anyone experienced same issue, and have an idea of what is going wrong here? Any feedback are appreciated.

Best Regards,

/Løjmann

[Gigazelle · Accepted solution]

If you're getting different visitorID's across different domains, double check the following:

• That you're using the same DTM container
• That the tracking server and tracking server secure variables are identical

If you've verified that the above are correct, Customer Care will be the best avenue to proceed from there.