NetWorker: How to configure email notification on Linux
Résumé: How to configure email notification on Linux.
Instructions
NetWorker server's deployed on Linux use the Linux mail 
mailx commands to send NetWorker logging through email. This functionality depends on non-NetWorker environment configurations.
Basic syntax of the mail command:
mail [-s <mail server hostname or IP>] -s "<subject>" -r <sender_email> <recipient_email1> [<recipient_email2>]
Specifying the mail server is not always required. In some environments, the mail server is picked up by the recipient email address specified.
Example:
mail -s "${NSR} ${policy} ${workflow} ${status}" -r bkupadmin@amer.local backupadmin@dell.com
Before configuring email notifications in NetWorker, the mail or mailx command must be run from the NetWorker server's command line to ensure that emails are received.
Example:
When you run the mail command, it drops to a new line with no prompt. You can type a test message (as shown above). On a new line, enter . (period) which returns End Of Transmission (EOT).
Check the recipient's email inbox (and spam folders) for an email. If an email message is received, you can configure notifications in NetWorker:
Informations supplémentaires
Troubleshooting:
If the email message is not received, there are a few steps which can be performed to identify the issue.
1. Is the postfix service running on the server:
systemctl status postfix
b. If it is not running, can it be started?
systemctl start postfix
c. If any issues are observed, check the service status and messages:
systemctl status postfix
journalctl -xe
d. Confirm if postfix is configured to start after a system reboot:
systemctl enable postfix
systemd. If it was already enabled, no message is outputted and the prompt returns.
2. If you have specified a `-S <mail server hostname or IP>`, confirm that you can reach the mail server from the NetWorker server.
nsrports -t mailserver_hostname -p 25
Example:
Other methods for troubleshooting resolution and connectivity:
nslookup mailserver_fqdn
nslookup mailserver_shortname
nslookup mailserver_ip
c. Check the /etc/hosts file for any entries for the mail server. If any incorrect entries are found, set the correct IP address or remove the entry:
cat /etc/hosts
curl -v mailserver_hostname:25
Example:
mailq
Example:
mailq command does not return anything, then the mail queue is empty.