"Temporarily rate limited" ? from Google in mail relay.

  • Posted on September 4, 2014
  • guiceAsked by Philip G

For a short period, I’ve setup Postfix mail relay on my vhost to forward my email to my gmail account. Mind you, I’ve had this email address and domain for over 14 years – it gets a lot of spam (which is a big reason why I use Gmail for its awesome filters).

While watching the logs, I got this message (pretty quickly) from Google’s SMTP server:

Our system has detected an unusual rate of 421-4.7.0 unsolicited mail originating from your IP address. To protect our 421-4.7.0 users from spam, mail sent from your IP address has been temporarily 421-4.7.0 rate limited. Please visit 421-4.7.0 to review our Bulk 421 4.7.0 Email Senders Guidelines. f14si1032016icj.42 - gsmtp (in reply to end of DATA command))

(I’ve since moved the MX record back to the original shared host to insure mail works)

The thing is, I’m not bulk emailing. I’m simply trying to setup a mail relay for my custom domain. Google saw “an unusual rate (was actually only about 5) of unsolicited mail” being forwarded over simply because my address is spammed … a lot.

Is there anything I can do to alleviate this? The need of a mail relay host is actually a huge issue. This is preventing me from fully moving off my current shared hosts (A2Hosting & Dreamhost).

Show comments

Submit an answer

This textbox defaults to using Markdown to format your answer.

You can type !ref in this text area to quickly search our full set of tutorials, documentation & marketplace offerings and insert the link!

Sign In or Sign Up to Answer

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

Want to learn more? Join the DigitalOcean Community!

Join our DigitalOcean community of over a million developers for free! Get help and share knowledge in Q&A, subscribe to topics of interest, and get courses and tools that will help you grow as a developer and scale your project or business.

Did you set a SPF record and set up DKIM? Email with out them will often run afoul of Gmail:

To ensure that Gmail can identify you:

  • Use a consistent IP address to send bulk mail.
  • Keep valid reverse DNS records for the IP address(es) from which you send mail, pointing to your domain.
  • Use the same address in the ‘From:’ header on every bulk mail you send.

We also recommend the following:

  • Sign messages with DKIM. We do not authenticate messages signed with keys using fewer than 1024 bits.
  • Publish an SPF record.
  • Publish a DMARC policy.

Check out this tutorial:

How To Install and Configure DKIM with Postfix

While I agree with the comments above, it seems to me the only mail being limited is relayed spam. If I originate a message on one of my severs it goes through with no problem at all. But I have sevveral domains and stopped trying to filter spam beyond using spf, dmarc and rbl lists several years ago and let google or yahoo filter my spam. I wonder if I can do any special processing on the messages that google is rate limiting with Postfix.

Wow, I find it hard to believe that one email address sending mail to google would be enough to trigger alarms.

Have you checked your ip to make sure it isn’t blacklisted on any of the common sites. Could be previous owner was a spammer.

How long has this server been in operation? Any chance it could have actually been hacked and indeed sending out spam