I have an old MTA, that effectively cannot do anything TLS related.
It is being used for a number of internal systems, of which a subset of them have stricter requirements, where they must only send mail, if the receiver is able to recive using TLS; the policy 'must'.
I would like to implement a scenario where I replace that MTA with a Postfix drop-in replacement on same IP, as the systems are not easily configurable.
I'd like to hear if it is possible to say that server A,B,C,D (based on IP address/hostname etc) can send using 'may' policy, but server E,F should use the 'must' policy, regardless of the destinations.
I can find a lot of information on smtp-tls-policy-maps that handles this pr. destination, but nothing based on 'pr-source'.
Can anyone hint to as if it's possible, and where I should look in the docs?
If not, can anyone point to another product where this might be possible?