Hi Experts, I have Mail Server in the Inside Network with an ASA 5506-X and LAN Router. Everything is working as expected, i want mail server be the only server to communicate on port 25 with outside network but when i tried to block computers inside LAN from communicating on port 25 with outside network,did it successfully and i was able to send mail and not receive mail with addition of this configs;
access-list mail_access permit tcp host x.x.x.x any eq smtp
access-list mail_access deny tcp x.x.x.x x.x.x.x.x any eq smtp
access-list mail_access permit ip any any
access-group mail_access in interface inside
Topology:
Internet>>Firewall>>LAN Router>>>Mail Server