Sabahattin Gucukoglu wrote:
I imagine it's more of an implementation robustness issue to support multiline greetings
given the current text of RFC 5321. However, Postfix's new postscreen daemon, docs
http://www.postfix.org/postscreen.8.html , seems to be relying on it to do its job. Also
does something else disturbing (in typical Postfix experimental fashion) which is to
disconnect clients just for not liking the initial "Teaser" banner. According
to the STANDARDS section, this is RFC 5321-stipulated stuff. According to my experience,
yeah, probably works for short enough timeouts, and I've seen plenty multiline greetings
in the wild ...
I don't like spam either, but does this not strike others as being really quite
dangerous thinking and uncertain games to be playing?
Only the good guys complain when are problems, not bad guys.
Per 8 years of on-going daily statistics, ~5-8% drop because they
don't understand multi-line responses. There are all bad guys with a
two exceptions in the past, both good guys who quickly fixed their bug
once they were made aware. No one needed to be shamed and a serious
implementation is stubborn to fix it, they should be shamed. Its not
your problem, its theirs.
A server could of course have an connection IP whitelist to avoid
sending extended welcome responses. But the problem isn't with known
associations, its the anonymous world that is a plaque.
In my opinion, one of the strongest defense against spam is enforcing
or mandating SMTP compliance. Once you relax, it invites problem and