Address Assignment Question

Seth Mos seth.mos at dds.nl
Mon Jun 20 16:40:48 CDT 2011


Op 20 jun 2011, om 23:24 heeft Tony Finch het volgende geschreven:

> On 20 Jun 2011, at 16:26, Jérôme Nicolle <jerome at ceriz.fr> wrote:
>> 
>> But most RBL managers are shitheads anyway, so help them evade, that'll be one more proof of spamhaus &co. uselessness and negative impact on the Internet's best practices.
> 
> An organization that blocks 90% of spam with no false positives is incredibly useful.

Using a greylisting system is equally effective without the black list part.

My milter-greylist installation is aimed at allowing as much mail through as it can, instead of the other way around. Milter-greylist has a nice urlcheck feature and/or ldap verification for users. In my case it's a PHP script.

If I can verify the IP to be inside a /22 of the MX records, www records or domain records that is sufficient to bypass the greylisting. The timers are also quite lenient. Just 15 minutes of wait is enough, of they are persistent if we've seen them before by domain. We get the email regardless and phone calls are rare, and I never run the risk of never getting the email.

This has turned out to be a really effective way to allow normal email through without much delay. After just 2 days at work it's whitelisted over 75% of the active domains we do business with.

We have about 17 domains and I know what the poster is asking, we've been emailing our customers before, subscribed customers none the less. We've had our share of blacklisting before. And we even sent the emails with unsubscribe links.

But some of them will click the "report this as spam" link in their favourite mail agent as a means to unsubscribe. I mean, clicking a link is hard. The end result is that we end up on various block lists. It's a good thing that the email servers at large isps are often sensible enough to let the email through.

Some of the smaller ones had rather odd draconian limits set. This makes the situation for all of us worse.

Regards,

Seth



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