I think I could have been clearer with my message. It wasn't intended as
either a criticism of the ietf list management (in fact, I use precisely the
same anti-spam technique) or a request for help with configuration of my
mailservers (I may not be the sharpest knife in the drawer, but usually I can
figure these things out on my own).
Instead, I was presenting what I thought was an interesting example of a
subtle problem that can come up in ipv6 deployment.
The mailserver in question uses a default redhat enterprise build (actually
centos). ipv6 is either enabled by default, or just has a single check box,
with no further information. The fact that ipv6 is enabled so trivially
carries the implication that just enabling ipv6 won't actually damage
anything.
Now I know different. Just enabling ipv6 on an otherwise correctly
configured and functioning ipv4 box *will* cause damage -- it will cause mail
that would have been delivered to not be delivered. I could be wrong, but
this strikes me as a trap that lots of people could fall into.
As I mentioned, my servers actually do reject mail if they can't find a
reverse dns for the senders IP. Some of those servers use ipv6; in light of
all
this I'm going to have to rethink that decision. For a server, the
combination of enabling ipv6 and using this particular anti-spam technique
may drastically increase the number of false positives -- especially as ipv6
gets more widely deployed.
Best Regards
Kent
_______________________________________________
Ietf mailing list
Ietf(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf