You're quite welcome though I should worn that I'm not an expert with it by any means. It sounded enough like what we needed to solve a problem so I installed it on a test box. The install was painful enough that I learned a bit more than I wanted to in the process.
There's a few more details and some comparisons between milter-ahead and Postfix's verify in the messages from Aaron and I. Skippy > Skippy: > > Thanks for you explanation of milter-ahead! I had never quite gotten my > head around that particular milter until I read your email. > > Jeff G. > > [EMAIL PROTECTED] wrote: >> Even without seeing the headers, its a pretty common thing for >> spammers to send their spam through secondary mail servers. From the >> volume of this that I've seen I assume that a fairly large percentage >> of the spam software does this automatically. >> >> The problem for the mail admin is of course that in a standard setup, >> the secondary has no idea what accounts are on the primary and so >> blindly accepts everything for the domain. >> >> In sendmail its possible to set up a mail filter that accepts the spam >> connection and holds it open while it queries the primary to see if >> its a valid address. If it isn't the secondary refuses the spam right >> then and never queues it. The package I've used for that is >> milter-ahead from www.milter.org. I don't know if a similar setup is >> possible with postfix. >> >> >> Skippy >> >> >>>Any chance you could post the headers of this email so that we could >>> get a better idea of what happened? >>> >>>Jeff G. >>> >>>Michael Hrivnak wrote: >>> >>>>I have a question that relates directly to a spamming experience I >>>> just had. >>>> >>>>I understand what an MX record is. I have setup multiple machines >>>> that will relay for my domain in the event my primary mail server is >>>> down. I did so by adding to those machines this in >>>>/etc/postfix/main.cf >>>> >>>>relay_domains = $mydestination mydomaincom >>>> >>>>All machines involved run Mandrake 10.0 or 10.1. That tends to work, >>>> but I found a problem. In theory, anyone on the internet can use >>>> these backup servers to send email to my domain. Someone could spam >>>> my domain all day and all night through those servers. In fact, >>>> tonight I received a spam email that came through one of those >>>> servers and even claimed to be from two accounts (which don't >>>>actually exist) on that backup server (why would an email be from 2 >>>> accounts anyway?). What can I do to prevent this? >>>> >>>>Thanks a lot, >>>> >>>>Michael >>> >>>-- >>>TriLUG mailing list : >>>http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational >>> FAQ : http://trilug.org/faq/ >>>TriLUG Member Services FAQ : http://members.trilug.org/services_faq/ >>> TriLUG PGP Keyring : http://trilug.org/~chrish/trilug.asc >> >> >> >> > -- > TriLUG mailing list : > http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational FAQ > : http://trilug.org/faq/ > TriLUG Member Services FAQ : http://members.trilug.org/services_faq/ > TriLUG PGP Keyring : http://trilug.org/~chrish/trilug.asc -- TriLUG mailing list : http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational FAQ : http://trilug.org/faq/ TriLUG Member Services FAQ : http://members.trilug.org/services_faq/ TriLUG PGP Keyring : http://trilug.org/~chrish/trilug.asc
