On 25/03/17 14:43, Wietse Venema wrote: > Postfix can be configured to try IPv6 before IPv4 (with > smtp_address_preference), but that feature is independent from > routing features such as transport_maps, smtp_fallback_relay, and > so on. That is, there are no ipv6_transport_maps or > ipv4_smtp_fallback_relay features. >
A slightly different approach: You don't try to favour IPv6 over v4. However - If transport selects an IPv6 address, the message goes directly. If transport selects IPv4, it goes via the smart-host relay. Would this work? It would be useful to me, as my (domestic) IPv4 address is listed in the Spamhaus Policy blocklist, whereas my 6-over-4 tunnel is "clean". Allen C
