I’ve been running a MiaB server for 2 years without any problems. Lately [for about 2-3 months] some of the users’ emails do not get delivered and they receive an automated mail like this one below.
For all of the mails I checked the recipients are @gmail users or use Google Apps. They even got this error while sending to one of my Google Apps domains, and the “is receiving mail at a rate that prevents additional messages from being delivered” is not true, as I’m not receiving more than 2-5 emails daily.
I do believe this is not a MiaB issue, but I’m out of ideas on what I could try.
Maybe Google sees a new email sent to one of its domains and thinks it’s not legitimate, because it’s not receiving constant emails from my box?
host aspmx5.googlemail.com[220.127.116.11] said: 450-4.2.1 The user you are trying to contact is receiving mail at a rate that 450-4.2.1 prevents additional messages from being delivered. Please resend your 450-4.2.1 message at a later time. If the user is able to receive mail at that 450-4.2.1 time, your message will be delivered. For more information, please 450-4.2.1 visit 450 4.2.1 https://support.google.com/mail/?p=ReceivingRate j68si7403187otc.44 - gsmtp
I was aware of Google’s support page, but I don’t think it’s relevant, as all the addresses we send to belong to small companies or individuals. There’s just no way they would be receiving 60+ emails per minute.
We can confirm that CSF is not preinstall on any of our droplet distributions, including Ubuntu 14.04.4. LTS.
I don’t really know next steps for this, but I saw there are a couple [like @kimusan] of users affected by this, so maybe they’ll find this useful somehow. If I find more info about this I’ll be sure to post it here.
For anyone looking into this, please share your findings.
I am using DO as well and it is a clean miab box as well. I remember back in the days where graylisting was popular I saw similar problems with misconfigurede serveres. Graylisting told them to wait a bit andd resend, they then sent another mail again eight away… And continued to do so over and over again. I cannot see how that could happen with miab though… Just noted that it looked similar back then.
I also have a clean IP as I’ve checked and rechecked it. I’ve been running it with minimal maintenance for two years [just upgrades] but these problems started a few months ago [I think it was in October 2016].
Searching for sent emails returns nothing - maybe I’m not allowed to view any reports prior to upgrading. All I hope is that I’ll be able to catch one of these errors and resolve the issue before my trial expires.