jason hirsh:
> I am apparently having an issue with some servers whose mail is being
> rejected because of
>
> reject_unknown_hostname
>
> the reject was shown here
>
> Aug 11 00:21:36 xxxxxxx postfix/smtpd[96422]: NOQUEUE: reject: RCPT
> from mail01a.yesbank.com[65.196.66.182]: 450 4.7.1
> <MTL01PPSMTP1.YESBANK.COM>: Helo command rejected: Host not found;
> from=<pbona...@yesbank.com> to=<di...@witheld.com> proto=ESMTP
...
> but no reject message went out... Is there a way I can esnure an
> error message goes out to the sender???
No reject message is sent out because your server answers with SMTP
reply code 450. This corresponds with a "Try Again" class error.
The SENDING MTA will give up after trying for several days. Only then
will the sending MTA inform sender that the message is undeliverable,
The 450 reply code means that the hostname lookup failed because
Postfix received no reply when it looked up the client hostname,
or when it tried to verify that the name really resolves to the
client IP address.
Wietse
