Google throttles own notification messages for domains routed through Cloudflare

[user22813]

I have recently moved several domains to Cloudflare (registration and name service). I have enabled mail routing, which seems to be working quite well save for one issue:

Google’s mail servers throttle Google’s own security notification messages (please see attached screen shot).

Have I misconfigured something? If so, why is it affecting only Google’s own notifications?

Is this a Cloudflare issue? A Google issue? Has anyone else experienced similar?

I would appreciate any advice on this issue.

Thank you!

[DarkDeviL]

@user22813

Is this a Cloudflare issue?

No.

@user22813

A Google issue?

The rejection message you see (attached screenshot) is, as you also mention, Google throttling the messages.

If you would call it a Google issue based on that, then yes.

@user22813

I would appreciate any advice on this issue.

Avoid using email forwarding, would be my advice.

Cloudflare (or any other email forwarding service) CAN TRY to deliver the messages to the final destination, Cloudflare (or any other email forwarding service) CANNOT force the final destination to take them, if they don’t want to.

See this (especially last section):

Email forwarding questions

Whether you call it Email Routing, or as with your words, “forwarding”, it would technically be referring to the exact same thing. Stuff like e.g. the massive spam, phishing and malware distribution going on out there., has provided us with the result that more and more providers have become strict in regards to what they (want) receive, but unfortunately haven’t been much clear to their users about it. Forwarding/(re)routing looks as a result, especially of that, to be a thing of the past. I…