The order of IPv6/IPv4 outgoing connection attempts is
not yet configurable. Currently, IPv6 is tried before IPv4.
Postfix currently does not support DNSBL (real-time
blackhole list) lookups for IPv6 client IP addresses; currently
there are no blacklists that cover the IPv6 address space.
IPv6 does not have class A, B, C, etc. networks. With IPv6
networks, the setting "
mynetworks_style = class" has the
same effect as the setting "
mynetworks_style = subnet".
On Tru64Unix and AIX, Postfix can't figure out the local
and always assumes a /128 network. This is a problem only with
mynetworks_style = subnet" and no explicit