Steffen Heil wrote:
>>RFC2821 specifically *ALLOWS* in greeting message rejections.
>>It does not make them unconditionally "the best practice".
>
>> 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.
>
> IMHO this is ment to allow deployment of systems that accept connection
> froms self-owned ip ranges only.
> However, you want to tell connecting servers that this system should not be
> connected for delivering mail.
... should not be connected *directly* for delivering mail
["Use your fallback relay" (your ISP smart host)].
> I still think this does not match and at least postmaster@ access should
> have priority over spam rejecting (which is propably your goal)
Some people insist on using "personal MTA" on DSL lines and send
directly whenever possible.
Multiple postmasters do not want to receive email from DUL ranges
because they hosts many "viral spamware".
I think that "554 Listed as DUL by service XXX" greeting message allows
to make both sides "reasonably happy" [blocking postmaster@ for DUL IPs
is a price to pay for it].
My objectives for DUL blocking:
* if message is sent by MTA then give MTA a chance to use fallback relay
* providing sending party info why email is not accepted so nobody
thinks that your mail service is "out of service".
It excludes "firewalling out" access to SMTP port
--
Andrzej [en:Andrew] Adam Filip anfi@??? anfi@???
Home Page
http://anfi.homeunix.net/
