Cloudflare not caching CNAME record

I have a subdomain which previously was pointing to a firebase hosting app through an A type record, Cloudflare use to cache almost al request, generating less than 10 MB of daily data usage on firebase hosting, while serving cache content most of the time. Now this subdomain was changed to a CNAME record, pointing to the same app, but since then I can see an increase of the download data usage in firebase, with almost 400 MB daily, which affects the cost. Should that be happening? Should not Cloudflare cache the content in the same way as it use to do it with the A record? What can I do to fix this? (returning to the A record is not possible)

If the CNAME points to Firebase and is not proxied, then the requests aren’t passing through Cloudflare so no caching (or other features) can take place.

What is the domain?

That is the thing, it is proxied in deed. That is the weirdest thing.The subdomain is booking.vertice.travel. Would you please help me with this?

Hi there, did you have the chance to take a look into my issue?

Cache is definitely working:

Best to look through your Cache Analytics (if you’re on a paid plan), filter for MISS, pick the top URL, click Filter, then remove the MISS filter. After that you should see how often that file is requested. If it’s not requested often, that may explain the low hit ratio.

This blog post does a good job of explaining cache ratios:

If you enabled Tiered Caching, the Smart Topology should go a long way to improving cache hit ratio for popular assets.

One other thing (if you’re already using Smart Topology Tiered Cache)…With a single A record, that’s a Single origin. Some CNAMEs resolve to many origins, which distributes the upper tiers in Smart Topology, causing a lower HIT ratio.