On 1/4/2015 5:43 PM, rogt3...@proinbox.com wrote: > My question is about usage. > > Is there a reason NOT to simply use the 521 hangup coes for ALL the spamhaus > hits from 127.0.0.2-11 ? It seems to me like all of those would be good > candidates.
The 521 response code is a fairly recent invention. It's possible a "real" mail server will not recognize the 521 code as a permanent failure, and continuously retry delivery of the unwanted mail. This isn't a problem with fire-and-forget bots that never retry regardless of the response. I don't know if you'll actually see this behavior, but that's the reason for the suggestion in the docs. Feel free to try it for yourself. -- Noel Jones
