Linux Services postfix

Install of all web apps postfix enabled, but won’t start service!
anyone resolve this problem?

Below steps will work .

yum install postfix -y

vi /etc/postfix/main.cf


myhostname = smtp.example.local

mydomain = example.local

myorigin = $mydomain

inet_interfaces = all

inet_protocols = all

mydestination = $myhostname, localhost.$mydomain, localhost,

mynetworks = 172.16.238.11/24, 127.0.0.0/8

systemctl enable postfix && service postfix start && service postfix status

systemctl list-unit-files | grep enabled