| I've had my setup running for so many years with minimal changes so don't have recent links handy but I'll give it a shot. This also points to the fact that while the initial setup will take some reading and effort, the ongoing maintenance year to year is basically zero. Start with a good IP address (static, not residential ISP, not on any block list). Search for sites that will help check this. https://mxtoolbox.com/ has many useful bits but there are others, try them all. Set up DNS correctly, forward and reverse. Set up postfix. Tons of guides out there, here's just one list: https://www.linode.com/docs/guides/email/postfix/
Read the various guides but most importantly read the postfix documentation in detail. It is very good and has everything you need to know. Configure postfix to enforce all sanity checks that it supports during the delivery connection phase. This alone will cut off nearly all spam! Install a local MUA (mutt would be my favorite) and you're up and running and should be able to send and receive, so test that thoroughly. Probably ending up in spam at this stage but should work. Mark it not spam in recipient. Note that if you had to register a new domain name, it'll likely be penalized as too new for a good while. Set up a cert (Lets Encrypt) for postfix. Configure SPF correctly. Read online guides but also read the RFC. Again, use online tools to validate your work. SPF is great. DMARC, DKIM are more controversial and less clear-cut useful than SPF. Read about them. I do set these as well. Set the notification email so you get reports (which aren't that useful but still). Use the online tools to validate. Set up Dovecot to enable IMAP. |