I had situation in past when one of my domain POP3/SMTP user/pass compromised. And someone connect to our server (SMTP) with that user account to send bulk of emails. I need to eliminate this sort of spam mechanism like in case if account compromised no one can send emails to others by using that user email address. I have quite some users on my domain which acts as POP3 and SMTP also. I can't block SMTP port on server because it's block outside world also to send emails to us. I thought another idea, to use openrelay like i need to add another server configured as open relay and on primary mail server i need to configure manualrouter e.g. if emails send from @example.com than relay to another.host.com which is finally responsible to send emails from that server and another.host.com i.e. on relay server i will allow only local users @example.com ip addresses only to connect via firewall.
So, outside world can send from primary mail server and within domain user can send emails from relay server. Please let me know if this approach is handy or is there any other better way of doing this. -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
