Steffen Heil wrote:
>>5?? code in *greeting message*:
>>makes some sending MTAs (sendmail and postfix) to try
>>delivery via "fallback relays" - it makes "5?? Listed in ...
>>as DUL" greeting a good way to say "use your ISP smart host"
>>for host that strongly insist on avoiding using smart host
>>whenever possible.
>>
>>P.S.
>>I "unintentional" change has happened in sendmail-8.13.2 (I
>>wrongly wrote about 8.13.3)
>
> You miss the point here.
> The rfc FORCES you to accept emails to postmaster@ and abuse@ for any
> domain, you are sending mail out for. And you need to do this conditionless.
RFC2821 specifically *ALLOWS* in greeting message rejections.
It does not make them unconditionally "the best practice".
<quote src="
http://www.ietf.org/rfc/rfc2821.txt ">
3.1 Session Initiation
[...]
The SMTP protocol allows a server to formally reject a transaction while
still allowing the initial connection as follows: a 554 response MAY be
given in the initial connection opening message instead of the 220. A
server taking this approach MUST still wait for the client to send a
QUIT (see section 4.1.1.10) before closing the connection and SHOULD
respond to any intervening commands with "503 bad sequence of commands".
Since an attempt to make an SMTP connection to such a system is
probably in error, a server returning a 554 response on connection
opening SHOULD provide enough information in the reply text to
facilitate debugging of the sending system.
</quote>
--
Andrzej [en:Andrew] Adam Filip anfi@??? anfi@???
Home Page
http://anfi.homeunix.net/
