[13398] in North American Network Operators' Group
Re: tcsender email bombing
daemon@ATHENA.MIT.EDU (Bradley Dunn)
Wed Nov 5 01:42:14 1997
Date: Wed, 5 Nov 1997 01:34:24 -0500 (EST)
From: Bradley Dunn <bradley@dunn.org>
Reply-To: Bradley Dunn <bradley@dunn.org>
To: nanog@merit.edu
In-Reply-To: <19971104212507.18912@denver.net>
On Tue, 4 Nov 1997, John-David Childs wrote:
> You may want to change your 451 errors into 571 errors at least for this
> particular domain. From RFC1893:
> > Nov 4 04:05:48 bconnex.net sendmail[4697]: Ruleset check_mail
> > (<tcsender@get-more-hits.com>) rejection: 451 <tcsender@get-more-hits.com>...
> > Domain must resolve
The usual reason cited for using 4xx errors instead of 5xx errors in this
case is that DNS failures can be transient.
Bradley
