What are the best tools for node.js monitoring?
What are the most important node.js metrics to monitor?
I have a good experience with IBM https://developer.ibm.com/node/monitoring-post-mortem/ and it is free. you also find here what to monitor.
PM2 monitoring tool for Zabbix
Node.js-powered daemon and utility that monitors a PM2 instance and sends status updates to the Zabbix server monitoring solution.