[CentOS] Relay with Sendmail

Fri Nov 24 10:34:46 UTC 2006
Denis Croombs <denis at croombs.org>

I need to only accept emails on my MAIN POP/IMAP server from 3 servers
(under my control (front line MX servers)) & local users who have local POP
accounts.

ALL other emails need to be blocked.
What is the best way of doing this ?

Thanks

Denis