[26497] in North American Network Operators' Group
Re: mail does bounce (was: Customers down?)
daemon@ATHENA.MIT.EDU (Christian Kuhtz)
Sat Jan 1 18:32:52 2000
Date: Sat, 1 Jan 2000 18:28:04 -0500
From: Christian Kuhtz <ck@arch.bellsouth.net>
To: Steve Sobol <sjsobol@NorthShoreTechnologies.net>
Cc: North America Network Operators Group <nanog@merit.edu>
Message-ID: <20000101182804.B29120@ns1.arch.bellsouth.net>
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In-Reply-To: <386E5E8F.FE20EF27@NorthShoreTechnologies.net>; from Steve Sobol on Sat, Jan 01, 2000 at 03:07:43PM -0500
Errors-To: owner-nanog-outgoing@merit.edu
On Sat, Jan 01, 2000 at 03:07:43PM -0500, Steve Sobol wrote:
> > I know for certain that Postfix and Smail will immediately bounce a
> > message when the domain is authoritatively non-existant. I'd be very
> > surprised and dismayed if sendmail and all other true SMTP mailers did
> > not do exactly the same thing.
I beg to differ.
> Sendmail most definitely does not, instead treating the error as a
> transient error, issuing an SMTP error code in the 400 series, and
> continuing to try to send the mail for up to five days (the default),
> or whatever the mail server admin configured for that particular
> server.
Yep.
> I think I like it better that way. Just because both nameservers are
> temporarily down doesn't mean the domain doesn't exist. :P
Or, worse, there's a glitch in the root servers or the registry maintaining
the authoritative data. Or everything's fine on that side and the mail server
receiving the message has been temporarily disconnect from the 'global truth'.
Better to queue temporarily and treat it as a transient failure than to drop.
That's almost always the best approach for loosely coupled systems, IMHO.
Cheers,
Chris
--
Christian Kuhtz Architecture, BellSouth.net
<ck@arch.bellsouth.net> -wk, <ck@gnu.org> -hm Atlanta, GA
"Speaking for myself only."
