I am trying to get a CNAME record proxied via Cloudflare
I have a webserver answering to
test.public.dev.euwest.azure.example.com (which I’ll call HOSTNAME_A) and set up a CNAME record to map it to
When enabling proxying for said record I expect requests intiated by Cloudflare to the origin server would use HOSTNAME_A, however if I try to connect via http I get a 404 error, via https it’s 525.
When trying to find answers about the 525 error I found SSL Error 525 with Proxied CloudFront origin which suggests the origin server should provide a valid certificate for HOSTNAME_B, since Cloudflare uses that to perform requests.
The community tips for error 525 seem to point to the same conclusion.
This goes against what is suggested by the documentation in this article Configuring an Amazon Web Services static site to use Cloudflare – Cloudflare Help Center where I would expect requests from Cloudflare to S3 are performed with the S3 address rather than the alias.
Am I correct in my assumption Cloudflare is using HOSTNAME_B to connect to my server? Is there a way to configure it to use the HOSTNAME_A?