Since nobody bothers to check previous posts (even from just a day or two ago), I won't bother with the details. All I will say is to learn the purposes of an MX record and how sending email works (and the differences). Hint: MX records have nothing to do with sending emails from your server. Just use a third party SMTP service in your config.hjson file.
Oh I read plenty posts. I am no expert so not always easy for me to understand relating their experiences to mine.
I was under the impression that postfix is all that was needed. And my config.hjson file is pointing to postfix. The issue that caused me to get confused and go down a very incorrect rabbit hole was that the postfix logs repeatedly error about connecting to my Mx record servers.
I read on github that it is a bug to use external smtp servers. You need to configure the postfix Container or wait for an update to use external SMTP.
For my instance, I already have an MXRoute account that I use for my personal email, so I just set up an account on there and pointed Lemmy at that. I've been down the road of self-hosting email, and it is a dreadful experience.
Granted, that was with full inboxes and POP3, just hosting the send part might not be so bad. But then you have to contend with possibly being on spam lists, and those are hard to get yourself removed from. If you have some cash to let someone else deal with that headache for you, I fully encourage taking that route.
Thank you to those that helped. As I figured I was being a noob and missing a key piece. Based off the instructions and my experience I didn’t realize I need to get a free or paid smtp service and point postfix to that server. Everything seems to be working now.
Summarizing the relevant parts of an eerily similar conversation I had the other day:
If you are using the built-in mail relay then you aren’t signing your mail with DKIM, don’t have SPF set up right, don’t have a DMARC policy, and don’t have FcRDNS, all of which basically any mail provider will require from you to even consider accepting your mail. Basically without all of that literally anyone can pretend to be whatever.com and send email from it. They really shouldn’t be shipping that mail relay at all IMO, it just leads to confusion. More than likely you would already know if you need a mail relay and be able to set it up yourself if so.
Sendgrid and Postmark are popular transactional mail services (which is what sort of email you will be sending, google that term to find more options). If you want some help getting your own mail server set up in a dockerized way I run my mail using docker-mailserver and if only set up for outgoing mail it is pretty easy to run, though you will probably run into deliverability issues as the large providers (google, microsoft, apple, etc) can be real assholes and assume anything from a non-large provider is spam. Feel free to ask me about how to do it if you are interested though, the more people run their own mail the better it gets for all of us.