> User of MTA5 wants to send mail to user of MTA1. MTA5 can do it directly or can ask any one of the intermediate MTAs to > pass on the mail so that it finally reaches MTA1. Say, for example,
> MTA-5--> MTA-6---> MTA-3---->MTA-2--->MTA-1 OR MTA-5---> MTA-3---->MTA-1
> Can this be achieved by Exim4. If yes then how do I configure all the MTAs?
It can be achieved very easily with manualroute router.
http://www.exim.org/exim-html-4.62/doc/html/spec_html/ch20.html
But *loops* will cause problems if you make full mesh manualroute network and use hosts_randomize.
Naturally every host should have their own manualroute table like (just to connect 'neighbours'):
Configuration at host MTA-5
Destination: MTA-1 (domain)
Path: MTA-3, MTA-2, MTA-6 (ip addresses in priority order)
...
Destination: MTA-6
Path: MTA-6, MTA-3, MTA-2
Without using hosts_randomize, and usign first option as first priority you have
manual shortest_path_first routing between hosts. And if some host 'fails' in-between
you have route around it (unless it is the destination host).
> Do I have to run a DNS (BIND) on each machine?
No Bind is needed unless you want MX based routing.
BR,
Jori
