Malcolm Weir wrote: > [...] > > The second MX is _strictly_ a fallback system. It will store and forward > messages for the primary, but it doesn't do the SMTP-level message > rejection. So it will accept pretty much anything sent to it, and then > shovel that on to my primary when the primary re-appears on the net. The > only circumstance that I want anyone to actually use it is if you cannot > contact the primary.
However, spammers usually send to secondary MXes after getting a 5xx answer from the primary. Hence the above defeats SMTP-leve rejection. I gave up my secondary MX as I reckoned it wasn't worth the hassle. Back to the subject, the odder multiple MXes are being encountered, the more special they deserve to be treated. IMHO, the AI engine that Sam spoke about should distinguish fallback from multihomed hosts, as the rules to mark/unmark some of them as BAD would be different. I'd expect most rules in the engine to be of the form: * How many routes must an MTA try before you call it MTA? * Yes 'n' how many times can a host fail pretending it just hasn't been tried? * Yes 'n' how many times must the spammers fly before they're forever banned? ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click _______________________________________________ courier-users mailing list courier-users@lists.sourceforge.net Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
