Hi, here we go :
I have a site with no DNS and the ISP's mailserver sitting behind a firewall.
Users have been connecting to the mailserver, but I would like to setup a Sendmail Unix mailhub, that would keep all local mail, and forward all other mail to the ISP's mailserver. Users can then check both pops while saving ISP bandwidth. i.e.
Domain : a.com
ISP Mailserver: 10.9.8.7
if user joe sends to firstname.lastname@example.org the mailhub at 18.104.22.168 will KEEP the message, while a message to email@example.com will be passed on by the mailhub to the ISP's mailserver for delivery.
How should I set up the conf files ?
Give a complete answer please :)