On Thu, Jan 21, 2021 at 03:15:24PM +0100, Jeff Abrahamson wrote: > I've been seeing this error for this one host. My first reaction was > that the host was incorrectly configured, but the IP (92.103.176.37) > reverse resolves to mail.mairie-carquefou.fr, which in turn resolves to > that IP. In addition, the MX for mairie-carquefou.fr is > mail.mairie-carquefou.fr (and mx3.mail.ovh.net). So I'm not really sure > what the "host not found" is complaining about. > > Jan 21 15:05:28 nantes-1 postfix/smtpd[6367]: connect from > mail.mairie-carquefou.fr[92.103.176.37] > Jan 21 15:05:29 nantes-1 postfix/smtpd[6367]: Anonymous TLS connection > established from mail.mairie-carquefou.fr[92.103.176.37]: TLSv1 with > cipher ECDHE-RSA-AES256-SHA (256/256 bits) > Jan 21 15:05:29 nantes-1 postfix/smtpd[6367]: NOQUEUE: reject: RCPT from > mail.mairie-carquefou.fr[92.103.176.37]: 450 4.7.1 > <SERVDMZMAIL.mairie-carquefou.fr>: Helo command rejected: Host not > found; from=<direction.gener...@mairie-carquefou.fr> > to=<x...@transport-nantes.com> proto=ESMTP > helo=<SERVDMZMAIL.mairie-carquefou.fr> > Jan 21 15:05:29 nantes-1 postfix/smtpd[6367]: disconnect from > mail.mairie-carquefou.fr[92.103.176.37] ehlo=2 starttls=1 mail=1 > rcpt=0/1 quit=1 commands=5/6 > > (I'm a bit confused about the SERVDMZMAIL in the helo. That host does > appear not to exist.) > > Any suggestions what to look at / if I've likely misconfigured something?
http://www.postfix.org/postconf.5.html#smtpd_helo_restrictions reject_unknown_helo_hostname (with Postfix < 2.3: reject_unknown_hostname) Reject the request when the HELO or EHLO hostname has no DNS A or MX record. -- Herbert
