By paul841204
I have hit the common issue of my DO IP address being blocked by hotmail, after 10+ years of trouble free usage!
They are completely unhelpful on why this is happening now so I am trying to sort it myself.
I have postfix configured to reject all unknown_sender_domain and I have noticed a lot of spam attempts from hotmail addresses in the logs. I wonder if there is a form of backscatter going on because I am then sending rejects?
Rather than send any sort of reject, can I configure postfix to silently discard the email and not send any reply? eg; I have ‘reject_unknown_sender_domain’ in main.cf
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Heya,
Just came across this answer and decided to write some general guidelines for anyone who comes across this in the future despite the old question.
Yes, you can configure Postfix to silently discard emails from unknown domains. You’ll need to modify the main.cf file, which should have a line that’s setting up your smtpd_recipient_restrictions. You can add the line ‘check_sender_access hash:/etc/postfix/sender_access’.
In the sender_access file, you can use the ‘DISCARD’ action to silently drop emails from specific addresses or domains. Here’s an example:
hotmail.com DISCARD
You should run postmap /etc/postfix/sender_access after every change to the sender_access file. Finally, don’t forget to reload Postfix’s configuration using the postfix reload command.
Please confirm that you understand the consequences of implementing this change. This will discard every single email from hotmail.com without any notification. The sender won’t get a bounce message or any other error and will not know that their message wasn’t delivered.
You can learn more about this in the DigitalOcean tutorials, specifically How To Configure a Mail Server Using Postfix, Dovecot, MySQL, and SpamAssassin.
Hope that this helps!
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