Sooner or later you will to know what is inside the containers, and container monitoring will come in handy as it can look through the Docker containers to know what is going on there.
Here is a list of 6 helpful apps and services that give a boost to the sphere of monitoring: they all are different, from simple open source tools to enhanced monitoring services.
cAdvisor is a tool created by Google, and it is easy as it is. cAdvisor will generate useful information concerning basic behaviors of the Docker containers. This utility is easy to facilitate and use as it is easy as ABC, however, there are certain disadvantages: for example, you can check the content of the containers running on the same host, so multimode deployments won’t work here. Also you will have to eliminate gathered information of statistics singlehanded.
This tool is an open-source framework developed by Soundcloud. The main advantage of this tool is that it can elaborate massive amount of information from tremendous spectrum of sources, and the number of sources is unlimited.
Scout is a monitoring service that selects data from multiple hosts and has plug-in architecture. DataDog is practically the same thing as a Scout, however, it costs more ($15 per host instead of $10) but it proposes more detailed and flexible reporting.
Docker monitoring sometimes requires profound knowledge of system monitoring. Longentries has proposed a free logging service for Docker containers that monitor container metrics, detection and messages. The service is free of charge, however, there are some paid features that you can try out with help of 30-days trial. For example, this privileged paid mode is necessary if you want to monitor a restricted environment, such as Google Compute Engine.