ok - a dns name then, would cause the same problem.
basically the issue is
all requests come in via a front facing interface, but some requests go out of the other listening interfaces, I want to remove this by just having the instance listen on just the front facing interface, but I also think localhost host maybe used for some internal communication, hence 1 interface + localhost.
I understand that you are saying use a dns name, that's not a problem, IP/dns name, doesn't matter in this example.
I'm currently testing this just using the one interface, but I believe there are some jobs which are referencing the instance as "localhost".
it seems odd that you can say "LISTEN ADDRESS <blank>" and it will listen on multiple interfaces, or "LISTEN ADDRESS host" and it will listen on one host, but you can't do "LISTEN ADDRESS host1, host2"