Nagios: How to aggregate a large amount of notifications into one email notifcation?

I have a Nagios server which monitors many servers. There's a dashboard which has been coded in-house and it sends monitoring data using passive checks to the Nagios server. Whenever an issue occurs, the NOC team is being flooded with email notifications.

My aim is:

When an issue occurs, and even if the dashboard sends 100 notification emails to Nagios, I want Nagios to aggregate the notifications into one notification. Then I expect Nagios to send one more notification when the issue is resolved. How is it done?

Solution 1:

Flapjack is designed to help with this.

I'm pretty sure that Etsy's Nagios Herald address this issue. I'm told that what you want instead is the check_check.rb within the ruby-nagios gem. (H/T Ryan Franz)