On Thu, 2004-12-09 at 06:10, Ow Mun Heng wrote: > > I was just asking that question. Thanks for clearing that up. So, > effectively, it's just another form of greylisting then. > > Actually no. Greylisting is much different from SURBL or RBLs. Greylisting uses the SMTP RFC standards in a some what unique way. When an SMTP server connects to your server to deliver a message your server checks a database for a tuple that matches (IP address, sender, recipient). It has not been seen before and it is not in the whitelist a temporary failure code is returned to the sending SMTP server. Normal SMTP servers when they receive a temporary failure code will queue the message and retry it later. Zombie spam servers won't retry the message later. As a result your system does not accept the contents of the message and does not have to do any further processing to reject the spam messages. I have seen this block better than 95% of spam being sent to a system. So greylisting does not rely on any outside block lists of any type. I expect that it is much more efficient and more accurate than any block list as well. > > One suggestion, set things up to run spamassassin only on non mailing > > list messages. That will improve the speed of email processing on your > > system. I have seen very little spam in the mailing lists so this seems > > to be a reasonable process. > > That depends actually, Most mailing lists runs some sort of spam checks. > But some don't. eg: ACPI-Devel. Now, that one does not, it even has > viruses coming in. > That is bad! The list owners need to do a little work then. :) -- Scot L. Harris webid@xxxxxxxxxx Q: What's the difference between Bell Labs and the Boy Scouts of America? A: The Boy Scouts have adult supervision.
