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Description

This test case tests if the default MTA Sendmail is enabled by default and able to send emails.

Default MTA?
The current default MTA is Sendmail but this may change in the future see: Features/NoMTA.

Setup

  1. Ensure that sendmail package is installed.
  2. Ensure that other MTAs like: postfix and exim are not running.

How to test

  1. Switch to root user: su -
  2. Check if sendmail service is running and enabled at boot: systemctl status sendmail.service
  3. Install mail utility: yum install mailx
  4. Try to send email to root user:
    Ending the Message
    EOT is inserted into the terminal after ending the message with ctrl+D
    # mail root@localhost
    Subject: test
    test
    EOT
    
  5. Check if root has received the test email: mail
  6. Expected Results

    1. Sendmail must be running and active at boot, the output of systemctl should be like:
      # systemctl status sendmail.service
      sendmail.service - LSB: start and stop sendmail
      	  Loaded: loaded (/etc/rc.d/init.d/sendmail)
      	  Active: active (running) since Sat, 02 Jul 2011 12:39:41 +0100; 10s ago
      	 Process: 3244 ExecStart=/etc/rc.d/init.d/sendmail start (code=exited, status=0/SUCCESS)
      	Main PID: 3257 (sendmail)
      	  CGroup: name=systemd:/system/sendmail.service
      		  ├ 3257 sendmail: accepting connections
      		  └ 3266 sendmail: Queue runner@01:00:00 for /var/spool/cli...
      
      
    2. root user should receive the test email and the output of mail should be like:
      # mail
      Heirloom Mail version 12.5 7/5/10.  Type ? for help.
      "/var/spool/mail/root": 1 message 1 new
      >N  1 root                  Sat Jul  2 12:46  20/766   "test"
      &