On 8/1/2010 10:49 PM, Edward avanti wrote:
On Mon, Aug 2, 2010 at 9:45 AM, Edward avanti <edward.ava...@gmail.com <mailto:edward.ava...@gmail.com>> wrote: <SNIP> In 4.x.x above me, the sender are known to us, his hostname presented exist, but no PTR RR (he is get fixed but take time), it is we prefer to 5xx, so he and others like him not wait 5 days to find mail never went, I was think unknown_client_reject_code = 550 would be this solve, but not? Anyway to have this so? It appear from more investigation this cause is SERVFAIL always send 4xx, can postifx override to 5xx with setting for SERVFAIL ?
Why in the world would you want to 5xx reject on temporary errors? Postfix would be insane to offer such an option. You will lose legit mail anytime there is a DNS hiccup.
If you don't care about losing legit mail, you can use a check_client_access table and reject clients named "unknown", or use an external policy service.
http://www.postfix.org/SMTPD_POLICY_README.html -- Noel Jones
