On Mon, 13 Mar 2017 17:49:47 +0100 Andy Smith wrote: > Hi all, > > I have a some genuine emails getting marked with NO_DNS_FOR_FROM > from one particular domain and I'd like to know exactly why. I've had > a dig in the Spamassasin Dns.pm but I can't work out exactly what > process_dnsbl_result is doing. What exactly does it check WRT MX and A > records?
It does what it says it does, it checks if the envelope sender address has neither an MX nor A record. One complication is that SA has to work out what the envelope sender address is, see "envelope_sender_header" in the configuration documentation. If you have a copy of the email that failed on NO_DNS_FOR_FROM, run it through SA and see if the problem is reproducible. If it is run it through spamassassin -D and search for NO_DNS_FOR_FROM to see what address is being used.
