PagerDuty is awesome. We have a pretty complicated follow the sun rotation split into 3 time periods per day and 2 teams on opposite sides of the world. It would be a real PITA to manage this without PagerDuty. It’s super easy to integrate Nagios with PagerDuty. If you haven’t done it already, you can find the instructions here. The problem with PagerDuty’s Nagios integration is that their guide says it requires the enable_environment_macros variable to be enabled.