(TL;DR: make sure DNS lookups are enabled in esmtpd conf to avoid RDNS_NONE false positives in SpamAssassin.)
>> When running courier compiled with “--without-ipv6”, submit.C still formats >> the Received headers with brackets around the IP address, like so: >> ... >> Received: from mail-qa0-f47.google.com (209.85.216.47) > > how did you come to this? looking through my mail, seems that most of > systems does add brackets… I read through some of the RFCs and then looked at DJB’s stuff (http://cr.yp.to/immhf/envelope.html). I couldn’t find anything specified (since it appears to originally be a debug header). So then I took one of the messages, ran it through spamc, with and without the brackets. That one change triggers the rule difference. >> Our spam filtering software is chocking on the brackets (SpamAssassin’s >> RDNS_NONE gets triggered). > > it's not triggered because of the brackets. It's triggered because your MTA > does not reverse-resolve sender. SpamAssassin looks up the DNS when it only finds the IP address — but only if the IP address isn’t bracketed. Based on observation. Looks like SpamAssassin will skip that DNS lookup if the header contains the value. > my system adds: > > Received: from mail-wi0-f172.google.com (mail-wi0-f172.google.com > [209.85.212.172]) > > >> Admittedly, the true fix is getting SpamAssassin to be more tolerant in its >> parsing. > > Maybe you should remove -nodnslookup from TCPDOPTS in your esmtpd file? Ah ha! Yes! That makes the false positive for RDNS_NONE go away (at least, when courier is compiled --without-ipv6; I haven’t checked the other way). Thanks, Matus — much appreciated, and far better. I hadn’t realized that the ident string would’ve included more than just the IP address. -Jeff ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net _______________________________________________ courier-users mailing list courier-users@lists.sourceforge.net Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
