> I am in the process of setting up a second domain for mail, but am at a
> bit of a roadblock. When I check things with mxtoolbox smtp test,
> everything is correct on my primary domain, but on the second one I get
> a message "Warning - Reverse DNS does not match SMTP Banner". Reverse
> DNS is correct (I have seperate IPs for each domain), so the
I think you missed the BASIC_CONFIGURATION_README document which
among others covers the Postfix server hostname and IP address.
One Postfix server can host lots of domains on the same IP address.
There is no need to have a different IP address and SMTP server
banner for each domain.
If you must, you can operate separate Postfix servers for each
domain. In that case each Postfix server must have its own main.cf
inet_interfaces and main.cf myhostname settings. See