[Greylist-users] Adelphia vs greylisting

Dave Warren maillist at devilsplayground.net
Sat Sep 24 21:45:11 PDT 2005

Allan E. Johannesen wrote:

>Is there a list of broken MX of otherwise legitimate ISPs?  Do we all discover
>those IPs intependently?
greylisting.org has one at http://greylisting.org/whitelisting.shtml

>Greylisting is a great idea, up until the day the typical spam-relay infection
>software implements retries, but these incompetently run ISPs are a problem.
That's part of greylisting's benefit.  However, if you perform DNSbl lookups too, there are good odds that a zombie will get DNSbl'd before the expiry of greylisting -- It has some benefit even if the host retries.

I don't bother preemptively listing incompetent ISPs too much, they usually eventually retry and after that the triplet is whitelisted anyway.  If I get any complaints then I bypass greylisting without question.

About the only thing I'd like to preemptively whitelist is flight listings, auction listings, and other time sensitive emails, but the companies don't make it easy to get the IP and MAIL FROM information.

However, I have no problem explaining to a CEO (or client, in my case) that his flight notification from AA was delayed because AA refuses to tell me what email address their notifications come from.  It's different when I haven't previously made an attempt to contact that specific company yet, but luckily that hasn't happened yet.

They say you shouldn't say anything about the dead unless it's good.

"He's dead. Good."

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