We don't have this problem because we pass messages through spamassassin before they are even accepted into our system. If a message is very obvious spam, it's rejected (not bounced). That's way more efficient than accepting a message then bouncing it. It doesn't make much difference to our server whether it has to reject 10 or 10,000 messages from a spam source. Every once in a while we get flooded with spam from a single source and the load spikes. But there is a lot of give in the smtp protocol and we have never had any problems losing legitimate messages. In fact, we even do virus scanning before accepting a message into our system. That's a very CPU intensive process. If we ever had load problems, I'd just take that part out and scan it after its already accepted into the system. We have about 400 end users and our front end server is just a dual-core machine with 16 Gb of ram. Spamassassin is pretty efficient. I admit it kind of stinks but it probably is unrealistic to expect the ISP to do anything. If they have 10 million subscribers, they probably have 5 million bots on their network. -----Original Message----- From: Blind-sysadmins [mailto:blind-sysadmins-bounces@lists.hodgsonfamily.org] On Behalf Of George Bell Sent: Friday, January 04, 2013 5:55 AM To: Blind sysadmins list Subject: [Blind-sysadmins] Spam Attacks What do you guys do if attacked from one specific IP address owned by a major ISP (in the States!) We've had 4 attacks in the last couple of weeks, and the ISP's abuse@... Are failing to respond. I even telephoned them, and was told that they only communicate abuse issues via e-mail, and as a policy do not send out acknowledgements. George Bell Managing Director Techno-Vision Systems Ltd 76 Bunting Road Ind. Est. NORTHAMPTON NN2 6EE, U.K. Tel: 0160 479 2777 Fax: 0160 479 2726 e-mail: george@techno-vision.co.uk Web: http://www.techno-vision.co.uk <http://www.techno-vision.co.uk/> _______________________________________________ Blind-sysadmins mailing list Blind-sysadmins@lists.hodgsonfamily.org http://lists.hodgsonfamily.org/listinfo/blind-sysadmins