iptables flushed, edit firewalld, but port 25 still end up blocked.

Note, there's nothing in between AAA and BBB they are both connected to the same switch.

[root@AAA]# firewall-cmd --permanent --zone=public --add-service=smtp success [root@AAA]# firewall-cmd --permanent --zone=public --add-port=25/tcp [root@AAA]# firewall-cmd --reload sucesss 

port still end up closed. Why?

[root@BBB]# nmap -p 25 AAA Starting Nmap 6.40 ( http://nmap.org ) at 2016-07-22 16:43 PDT Nmap scan report for AAA (192.168.38.40) Host is up (0.00014s latency). PORT STATE SERVICE 25/tcp closed smtp MAC Address: 00:1A:4A:73:3A:12 (Qumranet) Nmap done: 1 IP address (1 host up) scanned in 5.57 seconds