On 18 Jul 2013, at 1:06, tswmmeejsdad . wrote:
Hi All,
Is there a way to change the NDR on postfix so that if we get an error
like
below where the MX record doesn't exist, customers get a NDR straight
away
instead of waiting the for the maximal_queue_lifetime which we have
set to
3 days?
maillog.1:Jul 11 15:19:36 MyMailServer postfix/smtp[22320]:
610865A761: to=<
abc....@wilsonhtm.com>, relay=none, delay=8.6, delays=0.04/0/8.6/0,
dsn=4.4.3, status=deferred (Host or domain name not found. Name
service
error for name=wilsonhtm.com type=MX: Host not found, try again)
Postfix is open source, so there's a way to make it do anything. If you
know how to write C. :)
In this case, you are asking for something that should not be done. In
this case the problem is not really that there is no MX record, since
there is an A record to fall back to, but rather that the nameservers
which are supposed to be authoritative for wilsonhtm.com are replying to
queries with answers that are not marked as authoritative. Downstream
from them, recursive resolvers translate that into a reply to clients
such as Postfix equivalent to an unresponsive authoritative server.
Because Postfix relies on the OS resolver and can't examine every
possible nuance of DNS breakage, it *wisely* treats such transient DNS
errors as transient. The failure to find a MX for wilsonhtm.com is in
DNS plumbing, not in the essentially unknowable DNS records for the
domain.
The solution to your problem offered in Postfix isn't an immediate
bounce, but rather a delay warning. Those are off by default, but if you
set delay_warning_time to a non-zero value it will result in the
classical Sendmail-like behavior of sending users delayed message
warnings that cannot be expected to comprehend. I sincerely wish you
good luck with that.
