Incoming Email: cannot open mailbox

[pHneutre]

@james I didn't realize it was necessary, thanks.
I set it up on the 10th of march at 17:49. From this moment, the Discourse logs hasn't shown any TCP timeout on 995 anymore. But mails remain ineffective.
These errors remain afterwards:

I suspect the SMTPServerBusy reveals a new problem?

[james]

Hello @phneutre

Can you share your Discourse configuration?

[pHneutre]

@james As soon as I understand what you mean by that

[james]

Hello @phneutre
Did you configure anything in discourse for incoming mails?
See: https://meta.discourse.org/t/troubleshoot-reply-by-email/42026

[pHneutre]

@james Ah yes sure.
POP3 polling enabled and :

Note: POP3 polling port was actually 9595 (and wasn't considered modified by discourse (no green dot)), so that explains the 9595 call (but why was there a 995 call too then?). I just changed it to 995 and tried again to send an email (and waited for the 5 min of polling period), but no luck.

[pHneutre]

Bumping this thread in case someone got an idea.

[nebulon]

@phneutre so if you open a webterminal into the app and run env | grep MAIL you should see all the possible connection details. Note that using mail as the email server domain, means the app will connect via the local route and hence does not necessarily need encrypted connection at all, if that helps with the discourse pop3 setup.

[pHneutre]

@nebulon

CLOUDRON_MAIL_POP3_PORT=9595
CLOUDRON_MAIL_POP3S_PORT=9995
CLOUDRON_MAIL_SMTP_SERVER=mail
CLOUDRON_MAIL_IMAP_SERVER=mail

So that was why the pop3 polling port was 9595 on Discourse. I reverted it to 9595 and tried again replying by email. Still nothing, and the timeout on 9595 is back (at least it's consistent).
Could there be a port conflict? How could I check that?

[nebulon]

If you open a webterminal into your app instance you can try telnet mail 9595 to see if telnet is able to connect on the pop3 port. You should see this:

root@c5a31d99-2479-4c15-9f9f-b10ed96a3886:/app/code# telnet mail 9595
Trying fd00:c107:d509::4...
Connected to mail.
Escape character is '^]'.
+OK Dovecot (Ubuntu) ready.

[pHneutre]

@nebulon I get exactly that (except for the IP address ofc).

[nebulon]

huh an yet if ou use 9595 with mail as the host in discourse you still get timeouts?

[pHneutre]

@nebulon
Yes:

What do you exactly mean by "with mail as the host in discourse" ? My Discourse settings are as above. Host is the default one (my) :

[nebulon]

Ah try mail as the hostname instead of the dashboard domain. This would resolve to the local IP of the mail server and not the external interface.

[pHneutre]

@nebulon This will move the whole cloudron instance's mail server to this name. Aren't there any references I should worry about when doing this? (we're hosting a bunch of services, I don't know all of them)

[nebulon]

Ah sorry, I might not have been clearly communicating. I was referring to the configuration within discourse, use mail there as the mail server host.

[jdaviescoates]

@pHneutre I could be wrong, but I think @nebulon is just suggesting that instead of my.solectic.cloud in the POP3 polling host field shown below, you just put mail

I could be wrong, but I don't think he's suggesting updating the Server location as per https://docs.cloudron.io/email#server-location

[pHneutre]

When changing POP3 polling host from my.soletic.cloud to mail (the name on the local network?), I get :

If I try mail.soletic.cloud (public address just in case?), I get:

[jdaviescoates]

I was just guessing, could easily be wrong. I guess @nebulon will have to be a little clearer/ more explicit about exactly what he's asking you to try