This might be slightly off topic but I have something kind of tricky and interesting in mind. I've been using a dummy IP address as my lowest MX record as a way of getting rid of bot spam. And it's worked fairly well but I'm trying to make it more interesting.
What I'm doing now is pointing the lowest MX to a second IP on my lowest MX server and what I want to do is open it up to a selected list of IP addresses. Every 5 minutes I'm going to query a MySQL database and create a list of IPs that will be allowed to talk to this lowest MX. All other IPs will be blocked and forced to retry the higher MX which talks to everything. I am not good with IP tables but what I need to do is perhaps create a new chain of some sort (?) that I can wipe out and reload with new values. I'll read the list and accept every IP in the list and then drop all other IPs. Of course if there's something that can do this reading data out of me database that would be great. But that's probably too much to ask. So - anyone have any ides on how to do this? BTW, Can't do a 4xx error because qmail servers will never retry higher MX records if the see a 421 error. So the port has to be actually closed. -- ## List details at http://www.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://www.exim.org/eximwiki/
