Setup email relay server using sendmail

<yambe:breadcrumb>Sendmail_server_configuration|Sendmail server configuration</yambe:breadcrumb>

Setup email relay server using sendmail

To setup email relay server using sendmail use following steps:

1. Install sendmail on relay server. Ensure that incoming and outgoing connections to TCP/25 are allowed. Further DNS queries for MX / A records should work correctly on this machine.

   yum -y install sendmail

2. Enable on startup

   service sendmail start
   chkconfig sendmail on

   On CentOS 7 'systemctl start sendmail; systemctl enable sendmail'

3. Allow access to specific clients by editing '/etc/mail/access'. After adding new IPs using CONNECT for RELAY, do

   cd /etc/mail
   make
   service sendmail reload

   for new settings to take effect.

   On CentOS7 use 'systemctl reload sendmail' instead

4. On clients mention SMART_HOST as FQDN of relay server. In case of postfix clients set relayhost to FQDN of this server

Refer https://www.freebsd.org/doc/handbook/sendmail.html