CentOS 7.x Enable submission 587 port for postfix

<yambe:breadcrumb>CentOS_7.x_postfix_configuration|CentOS 7.x postfix configuration</yambe:breadcrumb>

CentOS 7.x Enable submission 587 port for postfix

To enable Submission 587 port when TLS configuration for postfix for port 25 is already configured use:

1. Edit /etc/postfix/master.cf
2. Uncomment following lines:

   submission inet n       -       n       -       -       smtpd
   -o syslog_name=postfix/submission
   -o smtpd_tls_security_level=encrypt
   -o smtpd_sasl_auth_enable=yes
   -o smtpd_reject_unlisted_recipient=no
   -o smtpd_recipient_restrictions=permit_sasl_authenticated,reje

3. systemctl restart postfix
4. netstat -alnp | grep 587
5. To ensure that firewall is not blocking incoming connection to 587 try "telnet <server> 587" from a remote machine.

<yambe:breadcrumb>CentOS_7.x_postfix_configuration|CentOS 7.x postfix configuration</yambe:breadcrumb>