This will not work if you have an off-site MX or you have an off-site MX that doesn't have the same packet filtering rules that you do. It will time out to the first MX, and deliver to the next. If that next MX is off-site, it will be delivered there and you will just get the spam via that route.. :/ It's best done with sendmail rules, I suppose.
Read the msg below from Cyberpromo. It is valid for ISPs to block at the router level as well as the sendmail level as per Cyberpromo's mail. I figured some people here may be interested in this. :-)
Hank Nussbacher
---------- Forwarded message ---------- Date: Sun, 20 Apr 1997 18:11:33 -0400 (EDT) From: Mail AutoResponder <abuse@c-y-b-e-r-p-r-o-m-o.com> Subject: Response from Cyber Promotions
----------------------------Original message---------------------------- Dear Sir/Madam,
Thank you for taking the time to write to Cyber Promotions with your concerns.
Please be aware that this mailbox (abuse@cyberpromo.com) is read by many people in our company, including our senior management. The fact that your message garners e-mail from an auto-responder is to insure a timely response. It should not be an indication of a lack of consideration or concern.
CYBER PROMOTIONS' POSITION ON ACCEPTABLE USE POLICY FOR INTERNET CONTENT Cyber provides email services to a large number of customers, whom are supporting thousands of end users.
It is our position that the Internet is an open marketplace, where commerce of any and all kinds may take place in accordance with public demand. We do not believe censorship is the responsibility of an Internet service provider. It is not our place to censor customers' content or legitimate business practices. Messages originating from customer sites reflect the opinions of our customers and not necessarily those of Cyber Promotions.
SUGGESTIONS Cyber is a pro-active organization with goals of delivering the highest quality email solutions. Since we believe in continuous improvement, we will re-evaluate our position in light of the any new regulatory developments.
We appreciate that our position may not be agreeable to everyone. Further, we understand your interest in seeking a solution. With that in mind, may we suggest the following options:
- END-USERs - A variety of e-mail and filtering software packages are available on the Internet for end-users. For example, Eudora and procmail offer sufficient protection from e-mail of your undesired Internet sites. Or you can use the latest in filtering software, e-Filter, sold on Cyber's own web page at... http://www.cyberpromo.com
- ISPs - Your mail servers and/or router systems can be set to reject incoming spam or filter out offensive sites at the IP level. Sendmail and ccmail are a few examples of good systems which perform these functions.
Again, we would like to thank you for your valuable input, and wish you continued success in your Internet experience.
Best Regards,
The Cyber Promotions Staff
(Many of Cyber's policies regarding these issues have been adopted from our own backbone providers.)
-- jamie g.k. rishaw <jamie@iagnet.net> - Internet Access Group [www.iagnet.net] - Cleveland-Pittsburgh-Detroit-Columbus-Akron-Toledo-Cincinnatti-Dayton - Corp: (800) 637 4IAG / (216) 623 3565. DID: (216) 902 5455. FAX (216) 623 3566. Personal: jamie@@arpa.com || jamie@@null.net (Remove second @, nonspammers) =)