Kevin A. McGrail wrote:
I believe an MX was designed as a Mail Gateway record for machines not directly connected to the network. Therefore, since an A record is for machines that are connected to the network, an A record should be enough to allow for mail to be delivered.I think Gary asking something different. He wants to check if the "from" domain has an MX record.
I know in practice that using only an A record works and is frowned upon. I also know that an MX record has been expanded more and more. But from an RFC perspective though, I'm not sure it's "incorrect" to just use an A record without an MX record. Hopefully someone else can comment but in the meantime, I'm not sure it's a legitimate test for spaminess.
Sincerely, KAM
Am seeing some spam where the sender's From_ address's domain
doesn't have an MX record. Was considering noting that fact
in the header as an extra X- field, and then letting SA score
it negatively. Has anyone tried that sort of thing? Can
you offer some prototype code that does something like that?
I think this is a valid test, as how could you send an NDR to such a domain, and a simple "reply" obviously wouldn't work so well.
I wouldn't think you'd get many hits on this sort of test, anyone who's gone through the trouble of setting up a domain has probably also defined an MX record. But let us know if you do get any hits, I'm curious.
-lee _______________________________________________ Visit http://www.mimedefang.org and http://www.canit.ca MIMEDefang mailing list [email protected] http://lists.roaringpenguin.com/mailman/listinfo/mimedefang
