We use nolisting, greylisting and spamassassin. When we implemented greylisting we found that our processed message load dropped from ~40,000 messages per day to ~20,000 messages per day. A while later we implemented nolisting and our greylisting load dropped by virtually the same amount. I haven't done too much log trolling because i'm lazy but looking at the stats for the last week tell the following story: Total Messages Processed: 146373 Total Message Size: 2445MB Spam Messages Identified: 89108 (61%) Spam Data Volume: 552MB (26%) AFAIK greylisting and nolisting do work as our spam volume percentages were closer to 95% beforehand. Kind Regards Tim Price Technical Manager thepacific.net Ltd tim(a)tpnet.co.nz +64 3 5439095 TreeNet Admin wrote:
Nathan Ward wrote:
On 15/01/2008, at 11:23 AM, Gerard Creamer wrote:
eats our bandwidth
And if you're an access ISP with a mail service, you're going to be receiving that spam email, and not being able to charge your end users for downloading it :-)
I'm not sure that bandwidth is a reason for spam filtering, unless you're a really big mail provider or something.
"Because users want it" is a much better reason.
Does anyone have actual stats of what sort of percentage of their traffic is spam? I don't really have any easy way to get that right now, unless I make my mail server output message size stats in to log files, or something. I'm curious as to whether anyone else has an easy way to get it that I'm missing.
I know I'm small fry by many of your standards but here are the local figures for Jan 15th 2008.
(filters in order) RBL-Blocked 590 NX-rDNS 506 Other-Reject 385 SPF-Blocked 13 Viral 0
Spam-Trap Accepted 564 Delivered Mail 1533 Forwarded Mail 73
So spam, (blocked+trapped) is 1606/2058 -> 78% of all email yesterday. Seems to have been a slow day with only 564 trapped. Most months the traps hits 40K+ over the whole period.
Based on random enquiries of customers when they contact, I'd estimate somewhere around 1% gets delivered when it should not.
AYJ Treehouse Networks Ltd. _______________________________________________ NZNOG mailing list NZNOG(a)list.waikato.ac.nz http://list.waikato.ac.nz/mailman/listinfo/nznog