How to install an SMTP server on OpenStack?

• Firtst and foremost, you need to configure the yum  
• After configuration of yum use the following command to install SMTP server-

         install postfix use-sudo apt-get install mailutils
         configure postfix file-sudo nano /etc/postfix/main.cf

• Then run command-service postfix restart

• to send mail use command-

          echo "This is the body of the email" | mail -s "This is the subject line" user@example.com