Re: Networking -- use of two Internet connections for one server with round robin DNS -- web okay, but should I do mail this way too?
Erwan David writes:
> My mail server is behind a NAT gateway in IPv4, and directly connects
> in IPv6. What shoud I configure it for HELO : the name of the NAT
> gateway (for IPv4) or its own name (IPv6 only from outside) ?
When your IPv6 SMTP server connects to another IPv6 SMTP server over
IPv6 and attempts to deliver a message the other server knows nothing
about your NAT or your gateway or your IPv4. It has an IPv6 address and
it wants to see if that address matches up to the name in the HELO.