Re: [exim] Bogus HELOs

Top Page
Delete this message
Reply to this message
Author: Exim User's Mailing List
Date:  
To: Randy Bush
CC: Exim User's Mailing List
Subject: Re: [exim] Bogus HELOs
[ On Wednesday, May 25, 2005 at 13:21:08 (-0400), Randy Bush wrote: ]
> Subject: Re: [exim] Bogus HELOs
>
> > Your mailer's outbound SMTP connections will not (or "SHOULD NOT") get a
> > different address depending on where they're connecting to
>
> actually, in v4 they may, and in v6 some would contend they should.


Maybe in some (broken!) IPv4 implementations they might, but not in any
of the ones I use. :-)

(remember, the statement I made above is about alias addresses on a
single interface, _not_ multi-homed addresses on multiple interfaces)



> this is all a bunch of useless smoke anyway. present some usable
> fqdn in the helo and be done with it.


Come on Randy -- you of all people should know better than to give such
bogus, confusing, misleading, incorrect, and downright damaging advice.

It's this kind of bogus advice which has lead to the likes of hotmail et
al thinking they can get away with doing such stupid things, now to the
extent that they've been even trying to use totally invalid top level
domains in their greeting parameter (e.g. .ice).

Look, the real rule is _really_ VERY simple, and there's really _no_
valid excuse for not following it.

The SMTP client "MUST" greet with either its proper fully qualified host
domain name (one which resolves to an A record giving its source
address), or IFF there's no such name available then it may greet with a
properly formed domain literal address that matches its source address.

There are no ifs, ands, or buts here -- and never have been.

-- 
                        Greg A. Woods


H:+1 416 218-0098  W:+1 416 489-5852 x122  VE3TCP  RoboHack <woods@???>
Planix, Inc. <woods@???>          Secrets of the Weird <woods@???>