How do I monitor Docker containers?

Docker container monitoring with Dynatrace provides you with a complete picture of your Dockerized environments. Dynatrace provides container-centric perspectives on Docker images, services, and hosts.

The Docker overview page provides a summary of the most relevant information:

  1. The infographic at the top of the page displays:
    • Number of running containers
    • Top 3 containers consuming the most memory
    • Most recently started container
    • Most frequently used images
  2. The Average number of running containers section of the page provides deep insights into the dynamics of your Dockerized environment by showing you how the number of containers has evolved over the past 7 days.
  3. The Docker hosts section at the bottom of the page shows resource usage of individual Docker hosts. This information helps you make decisions about capacity planning and container provisioning.

Monitor Docker containers

To explore container resource usage, click a host in the Docker host list and then click the Containers button. This is information you could otherwise only get by executing a docker stats command.

On the Containers grouped by image name page you’ll see all containers of the same image running on the same host that are consuming the most resources. Provided metrics include:

  • CPU – CPU user divided by CPU system, expressed as a percentage.
  • Memory – Resident Set Size (RSS) and cache memory. RSS reflects data belonging to processes, while cache memory represents the data stored on disk that is currently cached in memory.
  • Traffic – both incoming and outgoing network traffic
  • Throttling – total time when a container’s CPU usage was throttled

Monitor Docker images

In large environments it can be a challenge to keep up with image versions deployed across hosts and to track the containers of a certain image version. The Docker images page makes it easy to identify hosts running containers of a specific image version. Here you can learn details such as when an image was created and its virtual size (cumulative space taken up by an image).

Monitor Dockerized services

Another valuable perspective is the Dockerized services page. Here you can view all Dockerized services in a list that includes insights into the load and response time of each service. You can correlate these metrics with the number of containers used to provide each service.

Enable Docker container monitoring

To activate Docker container monitoring:

  1. Make sure that you have a recent version of Dynatrace installed on your Docker hosts and review the list of supported Docker versions.
  2. Go to Settings > Monitored Technologies.
  3. Enable the Docker containers switch.
  4. If you haven’t done so already, also enable the Plugin manager switch and the Docker switch further down the list.

The Docker tile now appears on your homepage. Click the Docker tile anytime to access the Docker page.