If you are on a Cloudflare paid plan, follow these suggestions in this Community Tip for best practices for a Cloudflare CNAME setup / partial setup to enable cloudflare with external DNS.
In the event that you are simply not able to change your name servers due to organization policy or local DNS limitations, we support a CNAME setup. CNAME setup / partial setup is a manual process available to paid Cloudflare plans only at the Business or Enterprise level. With CNAME setup, authoritative DNS remains elsewhere, and one or more subdomains are delegated to use Cloudflare using CNAME DNS record(s). You do not need to use this if you’ve already changed nameservers to Cloudflare and want us to be your authoritative DNS provider. Remember, a CNAME setup is for Business and Enterprise plans only and shouldn’t be confused with setting up a CNAME record.
Do not change your name servers.
After creating a Cloudlare account and verifying your DNS records, submit a ticket with the domain you would like to set up via CNAME. Please include the line “CNAME setup domain: example.com” for faster review.
If you are on the Business or Enterprise level of service with a CNAME setup, you will need to add three CNAME records at your authoritative DNS provider to authenticate the SSL certificates for your domain. You can retrieve these CNAME records by contacting Cloudflare Support or you can use the Cloudflare API to query for them.
Note DDOS protection for attacks against DNS infrastructure is only available for the delegated records. Cloudflare’s security and acceleration benefits are only available on delegated subdomains, such as www.example.com. The root domain, such as example.com, cannot be protected or accelerated via Cloudflare. This is due to DNS RFCs.
If You Need More Help
This community of other Cloudflare users may be able to assist you, but to request a CNAME setup, you need to login to Cloudflare and then contact Cloudflare Support. When you contact support, make sure to include “CNAME setup domain: example.com” in the ticket .
Expert Comments Appreciated
This Community Tip will remain open for input from Community experts and those familiar with this issue. We really appreciate comments that start with words like: “The three things I always try”, or “Do this first” or “In my experience”.