Victor Duchovni:
> If one wants to avoid whitelisting bots that only connect to backup MX
> hosts, appropriate configuration in the backup MX postscreen. I am not
> sure how this part of the design works, is that we expect that bot to
> fail the test via the backup IP, or are we trying to not whitelist
> clients that never try the primary IP?
Enable whitelisting only on the primary MX address(es).
In other words, always fail the tests for non-whitelisted clients
on the non-primary IP address(es).
Wietse
