Email forwarding 451 4.3.0 No available upstream

I have set up email forwarding for one of my domains. All the DNS records are configured correctly. I’ve set up and verified several routes. Originally forwarding seemed to be working well. In the last few days most emails are not being forwarded and senders are receiving bounces.

I tested by sending a mail to a forwarded address through my own mail server and this is the postfix log:

48B9C158295: host[2606:4700:f5::11] said: 451 4.3.0 No available upstream. U2eKFBYZwltu (in reply to RCPT TO command)

Also, the email dashboard has entirely stopped logging. It looks like this:

It says email routing beta at the top of the page. Should it say alpha?

Thanks for reporting.

There’s known major issues with Email Forwarding for the last ~30 hours or so. It’s been escalated and we hope to see a resolution soon.

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I have the same error.
Mail forwarding was working fine. But all of a sudden it stopped forwarding mail.
Forwarding to my catch-all gmail account is still working.

I’m not sure what “escalated” means in this context, but the length of this downtime for a critical service like email seems unacceptable. Is there anyone from Cloudflare that can comment on this issue? Is there another thread somewhere where the issue is being tracked? Is there any official ETA on a fix?

I’m pulling the domain I have set up for Cloudflare email forwarding and setting up forwarding instead on my own mail server in the mean time. How many people depending on this service don’t have that option and aren’t receiving email?

NOTE: this does not appear to be the same issue as that being reported in this thread:

The error number is different and people in that thread are reporting that issue was resolved, but as of the timestamp on this message, the issue I am reporting is not resolved.

cc: @Walshy

That was regarding the linked 550.5.1.1 outage - since your issue hasn’t been resolved as a part of the resolution for the 550.5.1.1 issue, please open a support ticket and post the ticket number here.

If you’re on a free plan and can’t open support tickets through the dashboard, email [email protected] explaining the error & situation and post the ticket number you get from the auto-reply (it’ll likely be auto-closed if you’re on a free plan but that’s fine).

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Running a critical service on a platform still in beta status is probably not best practice. I have set up CF Email Routing on one domain where it won’t create a tremendous problem for me if the mail gets lost. This issue has made it clear to me that I made the right decision not to migrate any more important domains until the service is no longer in beta status.


Ticket number 2473848

A bot replied to the ticket with a bunch of generic SMTP config platitudes that are non-relevant.

This morning I received a reply to ticket 2473848 from a human, but I don’t think that the reply actually addresses the issue I reported.

Thank you for contacting Cloudflare Support. We’re sorry to read that you’re experiencing difficulties.

The error message you pasted here was from the Postfix log, the error seemed to be an upstream connection error between the server and Cloudflare. Have you tried to use normal web based email client such as gmail, hotmail to reproduce?

Email forwarding is still in beta, so all feedback would be welcomed. I wonder if you would like to setup with a less traffic domain or just a test domain to test out this feature? I also have 2 testing domains and they were working fine so far, in your case, by the sound of the description, it might be caused by networking related. So I suggest you use a non production domain, then try from the same environment again, we can run some tests to check if this is to do with networking related issue.

cc: @sven2