James B. Byrne:
> I am configuring a new Postfix-3.3.0 service to act as one of our
> public MX providers. The address of this new MX service has been
> published in our DNS but with a lower precedence (higher priority
> number) than our active MX service.
>
> Naturally enough there are countless spam bots regularly hitting the
> low priority MX services and so when I activate Postfix for testing we
> get numerous opportunistic connections. When we do we frequently
> (always?) get messages like this in the mail queue:
>
> Received by mx32.hll.ca (Postfix) id 002F8E7E3; Mon, 25 Jun 2018
> 22:13:17 -0400 (EDT)
> Date Mon, 25 Jun 2018 22:13:17 -0400 (EDT)
> >From mailer-dae...@mx32.hll.ca (Mail Delivery System)
> To postmas...@mx32.hll.ca (Postmaster)
> Subject Postfix SMTP server: errors from
> smtp1.e2mailb2b.info[208.234.16.120]
> Message-Id <20180626021317.002f8e...@mx32.harte-lyne.ca>
> Message text
>
> Transcript of session follows.
>
> Out: 220 mx32.hll.ca ESMTP Postfix
> In: EHLO smtp1.e2mailb2b.info
> Out: 250-mx32.hll.ca
> Out: 250-PIPELINING
> Out: 250-SIZE 20480000
> Out: 250-ETRN
> Out: 250-STARTTLS
> Out: 250-ENHANCEDSTATUSCODES
> Out: 250-8BITMIME
> Out: 250-DSN
> Out: 250 SMTPUTF8
> In: MAIL FROM:<upd...@e2mailb2b.info> BODY=8BITMIME
> Out: 250 2.1.0 Ok
> In: RCPT TO:<scott.kak...@hll.ca>
> Out: 250 2.1.5 Ok
> In: DATA
> Out: 354 End data with <CR><LF>.<CR><LF>
> Out: 451 4.3.0 Error: queue file write error
> In: QUIT
> Out: 221 2.0.0 Bye
>
> Note that 'In: RCPT TO:<scott.kak...@hll.ca>' refers to a
> non-existent mailbox address.
>
> For other details, see the local mail logfile
And, what is in the local mail logfile around the time that this
message was received on Mon, 25 Jun 2018 22:13:17 -0400 (EDT)?
> # postconf -f | grep notify
> notify_classes = resource, software
> Since I do not set notify_classes in main.cf these are the defaults.
You have "notify_classes = ... bounce ..." somewhere, otherwise
you would not receive the above SMTP session recording.
Try: postconf -P | grep notify_classes
Wietse
