How to: Enable sending mail with IPv6 addresses
The dns_ip6_lookup feature is disabled by default as of InterWorx Version 5.1.7. This means
mail will not try to deliver via IPv6, unless the following is completed:
From the command line,
/var/qmail/control/senderip6 must be created.
/var/qmail/control/dns_ip_lookup, run the following command:
echo 1 > /var/qmail/control/dns_ip6_lookup
If the file is missing or contains anything other than “1”, the feature will be disabled.
If dns_ip6_lookup is enabled, then the senderip control file can be used for binding a local ip6 address based on the mail sending domain name, much like the senderip file works for ip4 addresses.
/var/qmail/control/senderip6 must be configured similarly to
Following these steps will allow mail to be sent via IPv6.