tcsender email bombing
bradley at dunn.org
Wed Nov 5 06:34:24 UTC 1997
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: Ruleset check_mail
> > (<tcsender at get-more-hits.com>) rejection: 451 <tcsender at 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.
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