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Install postfix <strong>using the following command</strong> and then follow <a href=“http://www.cyberciti.biz/faq/postfix-receive-mail-on-specific-network-interfaces/”>www.cyberciti.biz/faq/postfix-receive-mail-on-specific-network-interfaces/</a>:
<br><pre>DEBIAN_FRONTEND=noninteractive sudo apt-get install postfix -y</pre>