Greylisting sucks
Internet, Networking May 8th, 2007… when you’re on the receiving end of it
776354139 2946 Tue May 8 07:06:14 mj@turner.org.za
(host mail.netbsd.org[204.152.190.11] said: 450
port-sparc64@netbsd.org
But seriously, although there are some valid criticisms of greylisting, it’s very effective at reducing spam, albeit at the cost of mail server and network resources. I just wish more mailing lists would make use of it – most of the spam I get these days is from lists that don’t have adequate anti-spam measures in place (Debian, FreeBSD and OpenBSD lists I’m looking to you!).
May 8th, 2007 at 8:49 am
Well, lists are supposed to be fast. Both reading/answering. If you start to greylist new users, it would remove the possibility to be fast, hence the whole idea of lists. (imho ofcourse).
And greylisting is only working until more mailbots etc gets the picture and actually, resends the mail.
Hence it’s not a working solution. I’d rather take the 1second spamassassin-tour and get the job done anyway, since it’s more useful than making users wait for 15-60mins for an adequate mail.
May 8th, 2007 at 12:54 pm
You’re 100% correct – greylisting does have some nasty side effects, delays being one of them. I also agree that it only works “for now” and doesn’t prevent spam from proper MTAs, but if it’s going to prevent my MTA even seeing the spam, I’ll keep promoting it while it continues to remain effective.
I do use spamassassin, but find that a combination of greylisting, certain (conservative) RBLs and rejecting mail from non-RFC-compliant MTAs stops the majority of the spam I receive even before my MTA accepts it.