Beyond that, I can't think of any difference between running docker-compose as a user or root. How to check if a docker image is configured to run as root (Linux) or Container Administrator (Windows). If you run docker-compose command as root or a different user, those host mounts may be a different path, and the files may be owned by a different UID, that may or may not map to the UID of your application inside the container. The reason I say 'little difference' is that a compose file can configure host mounts that have a relative path. cAdvisor provides a ton of metrics to the point that I limited the amount that actually get stored in order to prevent the database from getting bloated. I wound up using cAdvisor to gather Docker container metrics. You configure this user in the Dockerfile, docker-compose.yml, or your docker run -u CLI. Docker natively supports Prometheus and Prometheus can also get metrics directly from the Docker daemon, however the metrics they provide are a bit limited. I decided to run Prometheus (and Grafana for dashboards) in Docker to allow for easy deployment using Docker Compose.

It's the equivalent of systemd running as root and launching a program as a non-root user. I am currently using Prometheus to collect time-series machine metrics from servers operating in various VPCs. The Prometheus image uses a volume to store the actual metrics. This starts Prometheus with a sample configuration and exposes it on port 9090. The important detail is to run applications inside of your container as a non-root user. Running Prometheus on Docker is as simple as docker run -p 9090:9090 prom/prometheus. The dockerd daemon is typically configured to run as root, the user accessing this API makes little difference (there is rootless mode currently in experimental). See this answer for details on how to give users this access. You can configure docker to allow non-root users to access this API, just be sure you trust these users with root access on your host, since the API gives that level of access. By default, this API is only accessible to the root user on linux, so you often see people running commands with sudo. The docker-compose command connects to the docker.sock, aka docker's API, to run all container commands.

Prometheus docker run as root