In part 1 of this series, I introduced Prometheus and lay some foundations for monitoring a Sitecore container environment using Prometheus. In this post, I will show you how to collect and monitor the Host OS and container metrics exposed by Docker.
Why should we care about Docker the Host OS Metrics?
To monitor your containerized Sitecore application effectively you need to understand the health of the underlying system your containers are running on. To achieve this, you have to monitor the system metrics like CPU, memory, network, and disk also docker is starting and stopping containers so you need to know the state of your docker resource.
How to collect Docker performance metrics
Docker supports Prometheus OOTB and provides performance metrics you can collect and monitor, however it is disabled by default.
1. Enabling Docker Metrics.
First things first lets enable the metrics. Open the daemon.json file and add the metrics-address setting:
“metrics-addr” : “127:0:0:1:9323”
Apply and restart docker. Now you should be able browse to the docker metrics 127.0.0.1:9323/metrics and verify metrics are exposed.