On Tue, 2007-01-30 at 07:47 -0500, Joey wrote: > OK I caught this at the end and I'm seeing 2 potential tools to reduce spam. > > 1. is the non-answering host as the primary. Correct me if I'm wrong but > the delay would be almost non-exsistant because the time it takes for the > connection to timeout is almost non-existant and would be better then > greylisting which can cause huge delays based on sending servers not being > correctly configured. Not better, I think that the spams caught by this technic would have being caught by greylist. However, as they will not hit the greylist, it means less memory and bandwidth waste.
> > 2. I see the tarpit of creating a high ranking MX which would capture > information of spammers that would be dropped into a reject list. I have seen legimate mail comming a hight mx, specially grupos.com.br which is like yahoo groups. However, legitimate mail here represents 2%-5% so far. I would not just reject it, but penalise (+3 here) them in SA. > I basically dropped greylisting last week because of the headaches it was > causing with multiple sending smtp servers, and I have seen a huge increase > in spam, method one here sounds like a great replacement. Really? what greylist implementation are you using? milter-greylist (which I am using) permits whitelisting of hosts/domains/ips, has an autowhitelist for SPF enable servers, which covers most cases like the one you mention. It has also an relax setting that after one mail in a host has being whitelisted, it can enable all mails from that host, which would also prevents your problem automatically in a few days. (I dont really like this, though). -Raul Dias
