Gerben Wierda:
> I think I am using postfix defaults here.
>
> WHen a client is rejected because of a mssing reverse hostname, I see:
>
> Nov 21 15:37:02 mail smtp/smtpd[2168]: NOQUEUE: reject: RCPT from
> unknown[46.221.40.2]: 450 4.7.1 Client host rejected: cannot find your
> reverse hostname, [46.221.40.2]; from=<a95901...@rna.nl>
> to=<a95901...@rna.nl> proto=ESMTP helo=<[46.221.40.2]>
>
> And I was just wondering: why is that a 4xx message (temp failure) and not a
> 5xx failure?
Postfix WILL NOT report a DNS 'try again' error as a hard error.
Gmail used to make that mistake with their IPv6, causing me
to disable IPv6 for gmail.
Wietse
