I use TLS for my postfix and dovecot,and I ready test centos 7 mail server by various tools,result as below:
Priority: 5 Connection established: yes TLS: yes SSL: yes Cipher: TLSv1/SSLv3, Cipher is ECDHE-RSA-AES256-GCM-SHA384 Uses secure cipher: yes
Then I block port 25
in iptables
,but I cannot receive mail any more.
As I ready use TLS,which means I only use 587
or 465
,why blocking port 25
cause I cannot receive mail?