Configuring your Centreon to send emails
For your Centreon to be able to send notification emails, you need to configure a local smtp server. If your operating system is RHEL, CentOS or Oracle Linux, Postfix is already installed.
This page gives you an example of a possible configuration. Refer to the official Postfix documentation for more information.
Notifications commands are executed by the poller that monitors the resource: you need to configure the mail relay on all pollers.
We recommend that you use a dedicated email account to send notifications.
Step 1: Configuring Postfixβ
- In your server's terminal, enter the following command: - yum -y install mailx cyrus-sasl-plain
- Restart Postfix: - systemctl restart postfix
- Configure Postfix to run at startup: - systemctl enable postfix
- Edit the following file: - vi /etc/postfix/main.cf
- Add the following information: - myhostname = hostname
 relayhost = [smtp.isp.com]:port
 smtp_use_tls = yes
 smtp_sasl_auth_enable = yes
 smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
 smtp_tls_CAfile = /etc/ssl/certs/ca-bundle.crt
 smtp_sasl_security_options = noanonymous
 smtp_sasl_tls_security_options = noanonymous- myhostname is the hostname of the Centreon server.
- relayhost is the email server for the account that will send notifications.
 - In the following example, Centreon will use a Gmail account to send notifications: - myhostname = centreon-central
 relayhost = [smtp.gmail.com]:587
 smtp_use_tls = yes
 smtp_sasl_auth_enable = yes
 smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
 smtp_tls_CAfile = /etc/ssl/certs/ca-bundle.crt
 smtp_sasl_security_options = noanonymous
 smtp_sasl_tls_security_options = noanonymous
Step 2: Configuring the credentials of the account that will send emailsβ
- Create a - /etc/postfix/sasl_passwdfile:- touch /etc/postfix/sasl_passwd
- Add the following line (replace - username:passwordby the credentials of the account that will send the notification emails):- [smtp.isp.com]:port username:password- Example: - [smtp.gmail.com]:587 username@gmail.com:XXXXXXXX
- Save the file. 
- In the terminal, enter the following command: - postmap /etc/postfix/sasl_passwd
- For security reasons, change the permissions on the file: - chown root:postfix /etc/postfix/sasl_passwd*
 chmod 640 /etc/postfix/sasl_passwd*
- Reload Postfix so that chenges are taken into account: - systemctl reload postfix
Testing and troubleshooting email configurationβ
- To send a test email, enter the following command: - echo "Test" | mail -s "Test" user@isp.com- Replace - user@isp.comby a real email address: the recipient should receive the test email.
- If the user hasn't received the message, check the following log file: - tail -f /var/log/maillog
- To check that your Postfix service is running, enter: - systemctl status postfix- The results should look like this:  
Gmail configurationβ
If you want to send emails through a Gmail account, you will need to turn on the Allow less secure apps option on this account. See Less secure apps & your Google Account.