Configure Sendmail relay server - AWS Elemental Live

Configure Sendmail relay server

Use this procedure to set up a Sendmail relay server if your network doesn't accept open relay messages.

Step A: Gather the mail server information

To configure AWS Elemental Live to relay the notification emails through a mail server, you need the following information:

  • The hostname of the mail server

  • If your network doesn't have DNS configured, the IP address of the mail server

Step B: Install the Sendmail configuration tool

Install the configuration tool to help configure Sendmail.

To install the configuration tool
  1. Install the sendmail.cf configuration tool by typing the following at the command line.

    sudo yum install sendmail-cf
  2. When you receive a caution message asking you to confirm that you want to run the command, enter yes.

  3. When you receive the following prompt, enter y.

    Is this ok [y/N]:
  4. When you receive the following message, move on to the next step.

    Complete!

Step C: Edit the sendmail.lic file

Edit the sendmail.lic file to add the hostname of the mail server that is performing the relay.

To edit the file
  1. With a text editor, open the sendmail.mc file. If you use Nano, which comes installed on all AWS Elemental systems, type the following at the command line to open the file in Nano.

    sudo nano /etc/mail/sendmail.mc
  2. Locate the line that defines SMART_HOST. It's generally just past halfway down the page and should look like this.

    dnl define(`SMART_HOST', `smtp.your.provider')dnl
  3. Uncomment this line by deleting the dnl at the beginning and end of the line.

  4. Change the following text to the hostname of the mail server that is performing the relay.

    smtp.your.provider
  5. Save and exit the file. For Nano, press Ctrl+O to save and Ctrl+X to exit.

Step D: Check the hosts file

If your network isn't configured with DNS, add a static entry to the hosts file on Elemental Live.

To add an entry to the hosts file
  1. With a text editor, open the /etc/hosts file. If you use nano, type the following at the command line.

    sudo nano /etc/mail/hosts
  2. Add a line to the end of the file that has the IP address of the relay server, a space, and the hostname of the relay server. The following shows an example.

    10.24.34.2 ExampleMailHostname
  3. Save and exit the file. For nano, press Ctrl+O to save and Ctrl+X to exit.

Step E: Apply the changes

  1. To apply changes, enter the following command.

    sudo make -C /etc/mail

    The system responds as follows.

    make: Entering directory `/etc/mail' make: Leaving directory `/etc/mail'
  2. Restart Sendmail by typing the following.

    sudo service sendmail restart

Step F: Test the new configuration

Test the relay by having the system email you an alert notification.

To test the configuration
  1. If you haven't already, subscribe to global alert notifications as described in Email notification. Provide an email address that you have easy access to.

  2. Generate a fake alert. A simple way to do so is to create and start a channel with a simple UDP input and output with a fake input address, such as udp://1.1.1.1:1111.

  3. Check your email for the notifications message.

  4. If necessary, return the global alert notifications to your desired settings.