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Ask HN: How to Stop Gmail Rate-Limiting

6 points by foxylad ↗ HN
Gmail messages from one of our mail servers (190.92.179.88) suddenly started being rate-limited a week ago. This affects thousands of Google's customers, who are getting their booking confirmations over 24 hours late.

We comply with every part of Gmails bulk sender guidelines. Both servers are registered with Postmaster Tools and have 0.0% spam stats; both have PTR, SPF and DMARC records; all messages are DKIM signed; neither server is on any blacklists.

We've filled in the form referred to on Gmail's bulk sender guidelines page twice, with no response or effect, and are now faced with the common problem of transmitting meaningful information through the Google event horizon.

Is anyone else experiencing this? Has anyone solved this in the past? Any Googlers able to pull a few strings to help thousands of YOUR customers?

6 comments

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LinuxBender
How to Stop Gmail Rate-Limiting

I don't have a good answer for stopping it given what you have tried thus far, but one can reduce the impact by distributing the outbound SMTP to different SNAT's, CIDR blocks, data-centers or even AS Numbers depending on how complicated of a setup one is willing to support. Every SNAT of course needs FCrDNS and all the additional CIDR blocks would need to be included in your existing SPF but that should reduce the threshold in effect.

foxylad
The annoying thing is that this is obviously a setting within Gmail, because our other server is sending the same volume of messages without any issues. Right now it's getting slowly better so I'm not keen to set up extra servers for what I hope is a transient problem.

Other suggestions have been to send all Gmail messages via our working server, but that would cause a spike in it's traffic and I'm worried we'd get the exact same issue there.

Both Microsoft and Yahoo have responsive processes to solve this problem, it's frustrating that Google is so opaque.

LinuxBender
this is obviously a setting within Gmail

Absolutely. The thresholds are even stricter in Yahoo. In my former life I had to set per-domain rate limits in all the mail servers in all our datacenters or customers could not receive emails. The only other option would have been to relay to email campaign providers which do the same thing I mentioned above however our customer contracts prevented using third parties.

solardev
Maybe do a test with Sendgrid or Mailjet to see if they have more success? Generally Gmail hates small email providers... and Google doesn't care about anyone but its advertisers.
sethammons
Moar IPs. Spread your load over after warming up the new one.
kazinator
Don't rely only on mail for booking confirmations?

You need an alternative way for users to get their confirmations, and any associated documents, simple as that.

Those materials can be provided in a self-serve download area.