How do you monitor Node Micro services running inside of Docker Containers?

This article about "How healthy is your Dockerized application?" explains the trouble with monitoring, but it doesn't provide any good examples of how to actually monitor a microservice inside of the docker container.

We are currently using PM2 monit to monitor our microservices, but as we put them into docker containers we lose the ability to access this data within one screen for all the various microservices which each run in their own docker container.

Dockerswarm monitoring will tell us the state of the containers, but not the microservice running inside of them.

What's a solid proven way of solving this problem?

One commonly used solution(not container-specific) is to build a health check API within your service which tests all the functionality you want monitored (say availability of DBs and other dependencies) and the app itself, and returns some expected output (say : ). You can then trigger alerts from a monitoring service like Nagios if this API does not return an ok for all the services. This will also fail if the microservice itself is unhealthy.

This approach also has the benefit of running a functional test of your service (by hitting an API end point).

This approach does not cover some edge cases though - eg. the microservice runs (but particular APIs fail).

StackExchange DevOps Q#1195, answer score: 4