[CentOS] email Server for CentOS 7

Mon Oct 1 20:10:19 UTC 2018
Leon Fauster <leonfauster at googlemail.com>

Am 01.10.2018 um 17:37 schrieb Peter Eckel <lists at eckel-edv.de>:
> If you want to run your own mail server (there are good reasons to do so, I've been running my own services for many years now) be prepared for a learning curve, as mail is not as simple and straightforward as it looks. You should also run your own DNS in that case, as many modern features of secure mail services are tightly linked to DNS (e.g. SPF, DKIM, DMARC etc.). DNSsec is preferred. 

and for the sake of completeness; another acronym MTA-STS, 
a new additional standard https://tools.ietf.org/html/rfc8461