[82011] in North American Network Operators' Group
Re: OT? /dev/null 5.1.1 email
daemon@ATHENA.MIT.EDU (Todd Vierling)
Fri Jul 8 15:32:39 2005
Date: Tue, 5 Jul 2005 22:23:13 -0400 (Eastern Daylight Time)
From: Todd Vierling <tv@duh.org>
To: Jim Popovitch <jimpop@yahoo.com>
Cc: nanog@nanog.org
In-Reply-To: <1120614594.26011.2.camel@localhost>
Errors-To: owner-nanog@merit.edu
On Tue, 5 Jul 2005, Jim Popovitch wrote:
> > Generally there's little reason to run a secondary MX. Email will
> > queue if the sole MX is offline or unreachable. Email will queue at
> > senders' mail servers.
>
> The problem with the above is that your (or your users') email delivery
> is then dependent upon the configuration and timeouts of someone else's
> system (my system drops undeliverables after 1 hour).
True -- however, too many people have so grossly misconfigured secondary MXs
in "traditional" operation mode, in the face of today's blowback bounce spam
world. Traditional secondary MXs are going the way of open relays, *quick*.
The default recommendation I give anyone these days is to use no
secondaries, and let the sender's mail server queue it up, as that's the
fastest implementation path. As a second stage, and only if the expertise
and time is available, then a backup MX with some sort of recipient
validation at SMTP time can be implemented.
--
-- Todd Vierling <tv@duh.org> <tv@pobox.com> <todd@vierling.name>
