docker-exporter

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Installing docker-exporter on Raspberry Pi 5 / ARM64 ​

Two ways to run it — docker run or Docker Compose — plus a one-line Docker-group GID fix when the socket needs group access (the common case on Raspberry Pi and other hardened hosts).

The image is published to GHCR for linux/amd64 and linux/arm64:

ghcr.io/dlepaux/docker-exporter:latest

Pin a specific version (e.g. :1.4.0) in production rather than :latest.

docker run ​

bash
docker run -d \
  --name docker-exporter \
  -v /var/run/docker.sock:/var/run/docker.sock:ro \
  -p 9713:9713 \
  --restart unless-stopped \
  ghcr.io/dlepaux/docker-exporter:latest

The :ro on the socket mount is deliberate — docker-exporter only ever reads.

Docker Compose ​

yaml
services:
  docker-exporter:
    image: ghcr.io/dlepaux/docker-exporter:latest
    container_name: docker-exporter
    restart: unless-stopped
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock:ro
    ports:
      - "9713:9713"

Fixing Docker socket permission errors on Raspberry Pi ​

docker-exporter runs as UID 65532 (the distroless nonroot user). The Docker socket is normally owned by root:docker, so the container needs the host's docker group GID to read it:

bash
docker run -d \
  --name docker-exporter \
  --group-add "$(getent group docker | cut -d: -f3)" \
  -v /var/run/docker.sock:/var/run/docker.sock:ro \
  -p 9713:9713 \
  ghcr.io/dlepaux/docker-exporter:latest

If the exporter exits immediately or /metrics shows docker_exporter_up 0, a missing docker group GID is the usual cause — see Troubleshooting.

Rootless Docker

Rootless Docker exposes the socket at $XDG_RUNTIME_DIR/docker.sock, not /var/run/docker.sock — see Docker's rootless mode docs. Mount that path instead.

Verify ​

bash
curl -s http://localhost:9713/metrics | head
curl -s http://localhost:9713/health   # -> 200 ok

If container_memory_working_set_bytes reads zero in /metrics, that's a host cgroup-v2 / Raspberry Pi config issue (memory cgroups disabled by default), not this exporter — see Why cAdvisor shows zero memory on Raspberry Pi 5.

docker ps also shows a health status — the image's HEALTHCHECK runs the binary with --health, a TCP liveness probe to its own port on loopback (no shell, no wget). It only confirms the server is listening, though; the /health endpoint is what verifies the Docker daemon is reachable.

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