Hi and Merry Christmas to all
I am having a problem with my email server and would like some advice as to the best way forward.
I have run my own SMTP server for about a decade now (beginning at bytemark, but now hosted with Hetzner - which /may/ be the problem). The server (at tap.rlogin.net) runs postfix and dovecot on debian 10 and uses a letsencrypt TLS certificate to transmit mail securely. The server has valid DKIM and SPF records and is not listed on any RBL at mxtoolbox.com.
I have no problem sending email to any of the major email providers but recently I have had mail refused by two organisations. One is a small company which uses mimecast filters, the other is ntlworld.com (who use cloudmark).
The rejections I receive are "hard" 550 refusals with messages referring to the respective filter mechanisms. I have, of course, contacted the companies using these filters and neither are interested in doing anything about it - they simply refer me to the respective filter providers.
Here I enter the catch 22 world of email delivery in that I cannot send email to eiether cloudmark or mimecast - because they use their own products. This is a classic example of why RBLs are a bloody stupid idea, but hey.
To make matters worse, the preferred feedback mechanism for both cloudmark and miimecast is via on-line feedback forms. Feedback to cloudmark vanishes into a black hole and I have never had a response from them. Mimecast's is even worse in that it doesn't actually work ("internal server error" would you believe). So I'm a bit stuck. I have resorted to sending email to them from a free GMX account I have, but I should not have to do that (and I still await replies anyway).
So - I /believe/ (but have no proof) that the reason my mail server fails a "reputation test" is that it is on a network block used by many others, and which may include Tor servers for example. Certainly I have a Tor node on Hetzner (but on a different network block). It strikes me a simply lazy for any admin to block a whole range of addresses on the grounds that it /may/ contain problematic servers, but hey. admins can be lazy.
The reason I am seeking advice here is that some of you also run email servers (or may have dome so in the past). Ideally I would like to continue to run my own server. I like the control and flexibility it gives me. But it is becoming increasingly difficult to do so in the face of the kind of opposition I see. I see only two options.
1. I find a new VPS provider which can guarantee that its network will not be blocked by lazy idiots and I move to them.
or
2. I give up and move my email to a third party provider (such as Ionos)
I am reluuctant to do 2 because apart from the loss of control, I would have to pay for each and every email address I use, and there are several, spread across (currently) four separate domains, there are often limits on the size of the emailboxes, or number of emails you can send, and there are also often limits even on the number of /aliases/ you can have.
My current Hetzner server costs me less that three euros a month. I'd be willing to pay more (Bytemark used to cost me £12.00 a month) if I could be sure that I woudn't have to move again.
Does anyone have a recommendation for a good VPS provider that would meet my requirements? If not, does anyone have a recommendation for a third party email provider that can accomodate multiple domains and email addresses without charging stupid amounts?
Any and all advice gladly accepted.
Best for the New Year
Mick
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