d5eeb3e8af
I was looking into creating a backup mx server for a high availability mailcow setup. It seems that this is not easily done. While researching to find out how long an average SMTP server keeps trying to send to a server that is down I found that RFC 5321 advises at least 4 to 5 days. Mailcow has a custom setup of 1 day, which is very short. The user will be unaware for 5 days that his mail has not been delivered, which can be negative. But I still would like to follow the advice of the RFC. RFC 5321, in section 4.5.4.1, has this to say: Retries continue until the message is transmitted or the sender up; the give-up time generally needs to be at least 4-5 days. It MAY be appropriate to set a shorter maximum number of retries for non-delivery notifications and equivalent error messages than for standard messages. Postfix default is also 5 days: http://www.postfix.org/postconf.5.html https://tools.ietf.org/html/rfc5321#section-4.5.4
mailcow: dockerized - 🐮 + 🐋 = 💕
💡 Entwickler gesucht!
Wir möchten die Kuh clustern und noch sicherererer machen, daher suchen wir dringend Entwickler, die dabei unterstützen. Bis hin zur Festanstellung alle Möglichkeiten offen. Bitte meldet euch bei info@servercow.de
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