Thank you for reaching out.
I understand you are trying to configure CDN managed certificate for your custom domain for Azure CDN. You getting an error message "We couldn't find a DNS record for custom domain that points to endpoint. To map a domain to this endpoint, create a CNAME record with your DNS provider for custom domain that points to endpoint."
Based on your statement above
I'm assuming we need to add some kind of CNAME record to DNS for the authentication, but it doesn't advise what needs to be added.
Yes to onboard custom domain to your Azure CDN you add a CNAME record to the DNS which maps to the Azure CDN endpoint.
You can follow this document to help set-up HTTPS for the custom domain.
The CNAME record created should in following format
Name -> test.mydomain.com
Type -> CNAME
Destination -> mytestcdn.azureedge.net
You can follow the instruction here on adding this record to your DNS provider or map a temporary cdnverify subdomain to avoid any downtime.
We also have a production website that has a CDN, that runs from the same root domain, i.e prod.mydomain.com so i'm wondering if we add the CNAME record for configuring the test CDN/Website, are we going to impact the production CDN/Website as they are the same root domain?
The CNAME record creation should not affect the production website as the CNAME record created will resolve to mytestcdn.azureedge.net and will serve the test environment content.
Although it is highly recommended to perform any changes during maintenance period to avoid any downtimes.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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