On 22/01/2024 17:16 EET Steve Dondley via dovecot dovecot@dovecot.org wrote:
there is no user in the above line
Some characteristics of the problem that may offer a clue:
- happening with multiple users, not just the same one
- happens from different IP addresses.
bots detected
The problem is happening to real users on real devices who are reporting very real connection errors, not bots.
- happens about 3 to 5 times per day and the errors come in batches like above
- MS Outlook error is:
why is it a microsoft problem now ?
reported error (0x80042109): ‘Outlook cannot conect to your outgoing SMTP email server. If you continue to receive this message….blah blah blah
disable pop3 in dovecot, problem is then gone
The same problem happens on IMAP. Example from log:
Jan 21 01:51:55 ip-172-30-0-131 dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=87.xxx.xxx.xxx, lip=172.30.0.131, TLS handshaking: read(size=598) failed: Connection reset by peer, session=<ctMkJm8PM9RX7LDO>
Hi!
Ensure your config says
auth_mechanisms = PLAIN LOGIN
and that you do not enable "Secure Password Authentication (SPA)" on the client unless you've done the necessary preparations.
Aki