Pim Zandbergen:
Wietse Venema wrote:
I know of no RFC that says only whitelisted clients can send email
over IPv6.
Well, it's their policy. I can respect that, if their assumption that
senders
should fall back to IPv4 is valid.
2 - Increase smtp_mx_session_limit (default: 2) so that Postfix
will knock more doors.
I guess that is what made their assumption fail. I've upped this limit
to 5,
and now my messages are waiting to be unlisted at their greylist on
their backup IPv4-only MX. Looks promising.
After having reported to the ISP to have already fixed the issue in Postfix,
I got a message stating that they have decided to stop rejecting
non-whitelisted IPv6 addresses.
Thanks,
Pim
