Let users point their domain (subdomain) CNAME to the proxied domain

My application domain domain.com is proxied via Cloudflare proxy.

In my application, I want to let the users use their own domain (sub.userdomain.com) to use instead of domain.com. For that, I want to ask the user to point their domain CNAME in their DNS to the domain.com.

  1. Is it the best way to let the user point their domain by setting a CNAME?
  2. Will those domains work if the domain.com is proxied by Cloudflare and they use a different DNS provider?

You can only do this in Business and Enterprise plans.

  1. The article states that I need to manually add the subdomain in the cloudflare DNS as well thenafter a TXT verification is generated which I’m required to add to my DNS. My application has thousands of users and each user can point upto 5 subdomains, If I need to create records in the cloudflare DNS as well then it’ll not be feasible.
  2. If the subdomain being pointed by the user is not proxied in cloudflare, will it work for them?

If yours is set to :grey:, then you can do whatever you want with it.

In this case, will it work for DDOS protection? Like if I enable DDOS attack mode, will it work for the domain with :grey:

No. :grey: means DNS only so traffic will hit your server directly.