On Fri, Apr 26, 2013 at 01:39:19PM +0800, Feel Zhou wrote:

> Apr 25 10:02:24 shcx postfix/smtpd[21741]: NOQUEUE: reject: RCPT from
> mail.example.com[d.d.d.d]: 450 4.1.2 <some...@example.com>: Recipient
> address rejected: Domain not found; from=<some...@example.com> to=<
> someb...@sino-progress.com> proto=ESMTP helo=<mail.example.com>
> 
> dig sino-progress.com mx
> sino-progress.com.      40      IN      MX      10
> qiye163mx01.mxmail.netease.com.
> sino-progress.com.      40      IN      MX      50
> qiye163mx02.mxmail.netease.com.

> This domain already exist, why noqueue

Always with a new thread:

    http://www.postfix.org/DEBUG_README.html#mail

Best guess given scant information:

    http://www.postfix.org/postconf.5.html#reject_unknown_recipient_domain

    ... The response is always 450 in case of a temporary DNS error. ...

Best practice for most sites:

   Don't use reject_unknown_recipient_domain.

Note for this restriction to pass not only do the MX records have to
resolve, but the MX hosts have to resolve to network addresses.  Any
of this can tempfail.

-- 
        Viktor.

Reply via email to