May 19 18:54:40 2021 (8280) Using agent: <mailman.mta.deliver.Deliver object at 0x7fb49b143780> May 19 18:54:40 2021 (8280) IndividualDelivery to: nathanael@lumenliquid.net May 19 18:54:40 2021 (8280) Using agent: <mailman.mta.deliver.Deliver object at 0x7fb4974541d0> May 19 18:54:40 2021 (8280) IndividualDelivery to: nathanael@lumenliquid.net
The fact that these are the only messages says that the attempt to send that message via smtp raised no exception as exceptions would have been logged, yet you say there's nothing in the maillog so there was no connect to Postfix. What are your settings for smtp_host: and smtp_port: in the [mta] section of mailman.cfg?
I set nothing explicitly as the default options fit my needs, so localhost:25 it is to my knowledge. Postfix itself was configured by Plesk and the config for mailman3 was manually added as prescribed. A manual telnet on localhost 25 gives me the expected 220 message from postfix.
It says the message in queue entry 1621441049.4089153+6dff56673dc64b890dd352941267782c264586dd is handled but gets requeued as 1621441049.4628382+6a0437ea387a2508ad947c0a51712075cbdb6d2e which presumably is handled and requeued again ...
Ok. Then I just need to figure out why it gets requeued. That also explains why the out-queue folder keeps creating a single message with different filenames over and over. But the logs keep silent about the reason..
Ok I figured out what happened.. First I tried to get more infos by running the runner manually once. And indeed, now I see that the runner "can't connect to SMTP":
(venv) mailman@h2831057:~$ runner -C /etc/mailman3/mailman.cfg -o -v --runner=out:0:1 May 20 12:17:24 2021 (20303) out runner started. May 20 12:17:24 2021 (20303) out runner started. May 20 12:17:24 2021 (20303) Using agent: <mailman.mta.deliver.Deliver object at 0x7f8a51649be0> May 20 12:17:24 2021 (20303) Using agent: <mailman.mta.deliver.Deliver object at 0x7f8a51649be0> May 20 12:17:24 2021 (20303) IndividualDelivery to: business@lumenliquid.net May 20 12:17:24 2021 (20303) IndividualDelivery to: business@lumenliquid.net May 20 12:17:24 2021 (20303) Starting new HTTP connection (1): localhost:8000 May 20 12:17:24 2021 (20303) Starting new HTTP connection (1): localhost:8000 May 20 12:17:24 2021 (20303) Cannot connect to SMTP server localhost on port 25 May 20 12:17:24 2021 (20303) Cannot connect to SMTP server localhost on port 25 May 20 12:17:24 2021 (20303) out runner exiting. May 20 12:17:24 2021 (20303) out runner exiting.
Which turns out is the completely wrong error message. SMTP works fine, it is the connection before (localhost:8000) that fails. After some more digging on that particular error I found a thread that linked this error with the use of templates. And indeed, if I add a footer template to my working list, it stops working. If I remove the footer from the broken list, it starts working. So there is something wrong with the templates.
After some more digging I looked into the database how my footers were saved and indeed, if I did a wget on the url it timed out because it didn't work. I then dug a little bit more and found the setting "POSTORIUS_TEMPLATE_BASE_URL" which apparently you also have to set. I didn't know because it was mentioned nowhere in the starting guide. So I set it to the url of my frontend and bang, it works (after fixing the urls in the database aswell).
It would have been nice though to have a more refined error to figure this out. But its solved now and hopefully this will help someone else as well.
-- Nathanael Schneider