Tim Chown <t...@ecs.soton.ac.uk> writes: > The IPv4 rep for the same MTA is Good. > > http://www.senderbase.org/lookup/?search_string=152.78.0.0/16 > > Would be interesting to see why the IPv6 rep would be different. Spam from > that MTA would presumably go out over whichever protocol was available. > Perhaps because there’s a much smaller sample size on IPv6 (maybe 3% of our > outbound is IPv6 last time I looked) it’s more susceptible to a small amount > of email that’s deemed spam.
It might be related to the second bullet point here: http://www.senderbase.org/support/#problem=3 "Your IP exhibits DNS patterns that indicate compromise by a SpamBot. Make sure your DNS is configured according to the protocol for RFC2821, section 4.1.1.1 (http://www.imc.org/ietf-smtp/mail-archive/msg00827.html)" A gold star to anyone who is able to explain what they mean by that, ignoring the fact that RFC2821 was obsoleted by RFC5321 more than 5 years ago. Bjørn