While testing Discourse, I experimented with using an SMTP server and sendgrid. Both seem to have major drawbacks and I’d like to discuss with other Discourse admins how you’re dealing with sending emails.
The issue with using an SMTP server (self-hosted or something similar) is that in theory its IP address could be quickly graylisted or blocked by ISPs. If that happens, a percentage of Discourse users may not receive their important emails (password resets and account confirmations).
With sendgrid/mailgun the main drawback I see is that every email sent through those services gets a link at the bottom allowing users to unsubscribe and never be contacted again. From what I have learned, Discourse uses only one email setting for both sending administrative emails (i.e. password reset) and other emails like digests, notifications of mentions etc. What if a lazy user clicks on mailgun’s unsubscribe link instead of their own preferences on Discourse?
What’s your experience with email servers in real life? Do you think any of these drawbacks may have real impact on a forum with ~30k users?