On Sat, 2010-06-26 at 22:47 +0800, Ed Greshko wrote: > A while back I did some observations and found that greylisting was most > effective at cutting spam. I forgot to mention that we use greylisting too; I highly recommend this as well. It is difficult to tell how many greylisted messages were spams that never came in and how many were legit messages that were later retried. Messages that get blocked by a DNSBL never get far enough to be greylisted either (no point since we already know it's spam, why invite them to retry?) It should be noted that greylisting *will* cause some delays in legitimate messages, and the length of the delay is totally under the control of the sending server. Personally, I think any communication that can't tolerate a few minutes or even an hour delay should be sent by some medium other than e-mail (instant messaging, even a phone call), but that said, I do get a lot of complaints about delays caused by greylisting, so this should be borne in mind. Most people shut up when I offer to turn if off for them so they can instantly receive all their spam :-) --Greg -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
