On Sat, Jul 13, 2002 at 05:27:07PM +0200, Martin Ma?ok wrote:
> We do filter mail servers that doesn't have a reverse DNS record
> and we have experienced that the emails which get undelivered due to
> this are from 99% from spammers, broken emails from broken mail
> servers from broken networks and only ~1% of undelivered emails are
> just a "correct" emails from networks with temporary DNS problems and
> from badly configured networks or from people not sending emails
> through their providers (but directly from their dialup)

Or anytime you have some sort of temporary name resolution issue you
start bouncing mail.  That's stupid.  Far too many people have had this
problem on this list to be such a small problem.  Face it DNS is not
reliable and can't be used for authentication... which is what requiring
reverse DNS is in essence doing.

> Also note that RFC 2821 (SMTP):
> 
> ...
> 
> 2.3.4 Host
> 
>    For the purposes of this specification, a host is a computer system
>    attached to the Internet (or, in some cases, to a private TCP/IP
>    network) and supporting the SMTP protocol.  Hosts are known by names
>    (see "domain"); identifying them by numerical address is discouraged

You're taking that toally out of context.  No where does it say that
hosts must reverse resolve properly or that if they don't you should
throw away their mail.  It says for the purposes of the mail system
that it's best to refer to hosts by their name.  However in the context
of receiving mail it doesn't really matter.  That section was written
to discourage people from doing things like this:
[EMAIL PROTECTED]

> Spamassasin? Why not... but I guess it will stress the servers load
> even more and could cause more delayed delivering (which is sometimes
> really bad now with cooker@)

Spamassassin is already run on Mandrake's incoming email.  At least
that's my understanding.

-- 
Ben Reser <[EMAIL PROTECTED]>
http://ben.reser.org

We tend to see all wars through the lens of the current conflict, and we
mine history for lessons convenient to the present purpose.
- Brian Hayes

Reply via email to