Well, I spoke too soon. Outbound email works fine, inbound replies seem to work fine, but posting to a category’s email address is failing silently. I copy/pasted the address straight from the settings into a new email, so I know there are no typos.
My mail-receiver’s logs basically have three types of entries. The successful one, which was an emailed reply to an existing post, looks like this:
Sep 20 16:59:44 discourse-mail-receiver postfix/smtpd[277]: connect from server168-1.web-hosting.com[68.65.122.144]
Sep 20 16:59:45 discourse-mail-receiver postfix/smtpd[277]: NOQUEUE: reject: RCPT from server168-1.web-hosting.com[68.65.122.144]: 454 4.7.1 <[category]@discourse.[domain].org>: Relay access denied; from=<ryan@[redacted].com> to=<[category]@discourse.[domain].org> proto=ESMTP helo=<server168-1.web-hosting.com>
<22>Sep 20 16:59:45 policyd-spf[288]: : prepend Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=[redacted]; helo=server168-1.web-hosting.com; envelope-from=ryan@[redacted].com; receiver=discourse.[domain].org Sep 20 16:59:45 discourse-mail-receiver postfix/cleanup[281]: 4CCED114200: message-id=<20240920165945.4CCED114200@discourse-mail-receiver.localdomain>
Sep 20 16:59:45 discourse-mail-receiver postfix/smtpd[277]: disconnect from server168-1.web-hosting.com[68.65.122.144] ehlo=1 starttls=0/1 mail=1 rcpt=0/1 data=0/1 quit=1 commands=3/6
Other than that, there are two types of (what I assume are) errors, each of which repeats quite a lot. The first one looks like:
Sep 20 17:00:23 discourse-mail-receiver postfix/qmgr[124]: 5D162FC26D: from=<double-bounce@discourse-mail-receiver.localdomain>, size=960, nrcpt=1 (queue active)
And the other:
Sep 20 17:00:23 discourse-mail-receiver postfix/error[293]: 8DC3BFC141: to=<postmaster@discourse-mail-receiver.localdomain>, orig_to=<postmaster>, relay=none, delay=126622, delays=126622/0.05/0/0, dsn=4.4.3, status=deferred (delivery temporarily suspended: Host or domain name not found. Name service error for name=discourse-mail-receiver.localdomain type=MX: Host not found, try again)
And here’s what my mailq looks like, just entries like this one over and over and over:
3D07BFC23D 960 Fri Sep 20 06:42:23 double-bounce@discourse-mail-receiver.localdomain
(delivery temporarily suspended: Host or domain name not found. Name service error for name=discourse-mail-receiver.localdomain type=MX: Host not found, try again)
postmaster@discourse-mail-receiver.localdomain
Some of this looks like it has to do with emails that Discourse sends, which then get bounced back for whatever reason. Does mail-receiver have any sort of functionality to processes these bounces, or are they going to sit in the mailq forever?
Secondly, why do replies work, but email posting directly to a category does not? Thanks again for your help and your patience. 