Introduction Nagios is an open-source IT system monitoring tool. It sends alerts when critical infrastructure components fail and recover, providing administrators with notice of important events Prerequisites Implementation (1) Define email notification commands$ vi /usr/local/nagios/etc/objects/commands.cfg ======== Add /edit the below lines # ‘notify-host-by-email’ command definition define command { command_name   … Continue Reading How to enable email notifications for the Nagios alerts