I hope someone can help me.
I have new up2date Mailcow instance.
Szenario: old mail server: oldserver
new mail server: mailcow
Domain: example.com on both server.
I want to migrate all mail accounts from oldserver to mailcow, but cannot do it all at once.
So I configured the example.com Domain to be relayed to old server, for all non local accounts. And I create a Senderdependet Transport Maps and chose this in the domain setting.
Internally example.com is resoling to 10.10.10.10
But somehow postfix whats to use the public IP for example.com, so completely ignoring my senderdependend transport map. Is by design?
how can I force it to use the internal IP?