On Thu, Jan 12, 2023 at 03:51:35PM +0100, Wolfgang Paul Rauchholz wrote:
> I am trying to find an error for the lost connection error. I tried
> several different sources but don't seem to make any progress.
What do you know about the SMTP client system?
> Thank you for pointing me into the right direction.
>
> Jan 12 14:01:02 home postfix/submission/smtpd[7046]: connect from
> unknown[10.5.2.1]
> Jan 12 14:01:02 home postfix/submission/smtpd[7046]:
> Anonymous TLS connection established from unknown[10.5.2.1]:
> TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
The TLS handshake was completed successfully. The problem may not be
TLS-related.
> Jan 12 14:01:02 home postfix/submission/smtpd[7046]:
> lost connection after STARTTLS from unknown[10.5.2.1]
> Jan 12 14:01:02 home postfix/submission/smtpd[7046]:
> disconnect from unknown[10.5.2.1] ehlo=1 starttls=1 commands=2
The submission client disconnects without sending any SMTP commands
after the TLS handshake, not even EHLO to probe for SASL support or QUIT
to disconnect "politely". Perhaps it did not like your certificate
(unexpected hostname: DNS-ID SAN?...).
If you don't know who the client is, and they're not complaining, just
ignore this. If the client user is known/complaining, get more
technical details from the user, what error does the client software
report?
--
Viktor.
