Re: multiple relay servers

[Fred Morris]

If DNSSEC isn't required for the domain(s) in question (or at least 
postfix in this specific case) you might look at RPZ as a way of rewriting 
just a single record in the zone: https://www.dnsrpz.info/

On Wed, 21 Oct 2020, IL Ka wrote:

I think you can install the DNS server locally (on the same machine where
postfix runs) and configure postfix to use it


On Wed, Oct 21, 2020 at 1:42 PM Zsombor B:


I can' force the customer changing their DNS.

Any postfix solution?
[...]