On Mon, Aug 22, 2022 at 11:42:38PM +0200, Jaroslaw Rafa wrote:
> Hello,
> this just appeared in my Postfix log:
>
> Aug 22 23:35:50 rafa postfix/smtpd[28891]: connect from unknown[unknown]
> Aug 22 23:35:50 rafa postfix/smtpd[28891]: lost connection after CONNECT from
> unknown[unknown]
> Aug 22 23:35:50 rafa postfix/smtpd[28891]: disconnect from unknown[unknown]
>
> I don't understand the "unknown[unknown]" part. The square brackets should
> normally contain the IP address of the connecting client. Why is "unknown"
> there? How is it possible that Postfix did not recognize the connecting IP?
The connection was reset before Postfix finished accepting it. The
kernel did not report the peer address, because the peer was already
gone. Perhaps an nmap scan, or a *very* impatient client.
--
Viktor.
