Stay organized with collections
Save and categorize content based on your preferences.
This article is for developers who want to host server-side tagging in the
same first-party context as their website. Same-origin serving is a best
practice that lets you leverage the security and durability benefits of
server-set cookies. The below instructions apply for setting up same-origin
serving regardless of the Google tag deployed on your site (gtag.js or
gtm.js).
When you first set up a tagging server, it is hosted on a domain provided by the
cloud provider. When you use the default endpoint, it delivers data to the
server container, but runs in a third-party context. To unlock the benefits of a
first-party context, such as more durable cookies, your tagging server and your
website have to run on the same domain.
The table below illustrates how you can host a tagging server when the parent
website is hosted on www.example.com:
Same origin (best practice)
Subdomain
Default domain
Example URL
https://www.example.com/metrics
https://metrics.example.com
https://metrics.run.app
Server-set cookie access
Full access to security and durability benefits.
Full access to security and durability benefits.
None. Can only set Javascript cookies.
Setup complexity
Configure a CDN or load balancer to forward requests. May need to update DNS entries.