Usually header of received messages contains reverse resolution of sender mailserver as in this example :
Received: from posta.gemmo.com (posta.gemmo.com [85.18.107.12])
by EFA.gruppocomet.it (Postfix) with ESMTP id 90D13A0680
ping -a 85.18.107.12
posta.gemmo.com [85.18.107.12] con 32 byte di dati:
But in this case there is not resolution, it tell me unknown, but ping -a give me correct resolution so reverse ptr is set but efa was unable to resolve :
Received: from mail.e-integrationservice.net (unknown [83.221.116.117])
by EFA.gruppocomet.it (Postfix) with ESMTP id 58374A006D
ping -a 83.221.116.117
host117-116.static83.221.interbusiness.it [83.221.116.117]
Why this has unknown in receive header ?
-
nicola.piazzi
- Posts: 389
- Joined: 23 Apr 2015 09:45
Re: Why this has unknown in receive header ?
SOLVED
THis is maillog :
EFA postfix/smtpd[27776]: warning: 83.221.116.117: hostname host117-116.static83.221.interbusiness.it verification failed: Name or service not known
Dec 13 06:04:47 EFA postfix/smtpd[27776]: connect from unknown[83.221.116.117]
This occurs when the sender ip doesnt have an A record that match ptr record :
83.221.116.117 resolves to hostname host117-116.static83.221.interbusiness.it
But hostname host117-116.static83.221.interbusiness.it doesnt solve to anything
THis is maillog :
EFA postfix/smtpd[27776]: warning: 83.221.116.117: hostname host117-116.static83.221.interbusiness.it verification failed: Name or service not known
Dec 13 06:04:47 EFA postfix/smtpd[27776]: connect from unknown[83.221.116.117]
This occurs when the sender ip doesnt have an A record that match ptr record :
83.221.116.117 resolves to hostname host117-116.static83.221.interbusiness.it
But hostname host117-116.static83.221.interbusiness.it doesnt solve to anything