Postfix -How to configure multiple mail servers for Incoming and outgoing mails
As a part of migration I am proposing different scenarios to my organisation. One which is asked to prepare is to configure multiple mail servers to handle incoming and outgoing mails through different mail server gateways.
Say I have example.com, I need to have accept mails from incom.example.com and send mail from out.example.com.
can some one guide me what settings are needed on Postfix or on Qmail?
Thanks in advance.