Remote SMTP server rejects messages because of mismatch between outgoing ipv6 address and reverse hostname #149
Description
Some remote SMTP server are rejecting messages sent by mox because the IPv6 address used for outgoing connections does not match the reverse DNS lookup of the same IPv6 address.
Apr 05 17:19:13 nixos-rpi mox[96706]: l=error m="permanent failure delivering from queue" err="permanent: 550 5.7.1 Client host rejected: cannot find your reverse hostname, [REDACTED_IPV6]" pkg=queue cid=18eaed64af0 [email protected] attempts=0 permanent=true code=550 secode=7.1 msgid=287 [email protected]
My ISP won't let me change the reverse DNS record for my ipv6, so I'm stuck to use only ipv4 for outgoing SMTP connections.
Is it possible the configure mox to use only ipv4 for outgoing SMTP connections? (and still accept incoming connections on ipv4 and ipv6).