On Sat, 2004-07-17 at 16:05, administrator(_at_)yellowhead(_dot_)com wrote:
At 09:44 AM 7/17/2004 -0400, "Roger Moser"
<roger_moser_spf(_at_)greenmail(_dot_)ch>
wrote:
So for us, you will always get a reverse lookup that does not
correspond to the forward lookup.
For the 'ptr' mechanism to match the reverse lookup does not have to
correspond to the forward lookup, but the forward lookup has to correspond
to the reverse lookup.
Roger
***************** REPLY SEPARATER *******************
Forgive my ignorance, but what good is that? It has absolutely nothing to
do with the the domain that sent the email. If I was a zombied machine
spewing out garbage using whatever for a domain name in the HELO, MAIL
FROM:, and From:, how would checking the PTR record
(207-34-104-6.ip.cal.radiant.net) against the "A" record [207.34.104.6]
provide any useful information?
What he means is that the reverse DNS lookup of 207.34.104.6 having a
PTR record pointing to 207-34-104-6.ip.cal.radiant.net is not trusted to
be reliable unless a forward lookup of the name
207-34-104-6.ip.cal.radiant.net yields an A record of value 207.34.104.6
(which it does).
This would have no effect whatsoever on anyone's SPF setup unless they
specified a PTR mechanism for the domain radiant.net, cal.radiant.net
etc. as indicating valid senders for their domain.
Paul.
--
Paul Howarth <paul(_at_)city-fan(_dot_)org>