My Zimbra server handles several domains.
For one of the domains, I'd like the server to accept incoming SMTP connections only from *one* given IP (our NATted internal network).
I cannot lock down using the firewall - as connections from the same IP (AND other addresses) bound for a different domain should be let through.
Can this be done without affecting how Zimbra handles mail for the other domains?
Thankful for any hints!