On Linux hosts, Docker persists container data within the host filesystem under the daemon's root directory, typically /var/lib/docker. This location houses image layers, container metadata, volumes, and network configurations.

To determine the current storage location and disk utilization:

df -h $(docker info -f '{{ .DockerRootDir }}')

Or inspect the directory contetns directly:

ls -la /var/lib/docker/

Within this directory, active containers store their writable layer contents in subdirectories managed by the storage driver (such as overlay2 or devicemapper). To identify a specific container's filesystem path:

docker inspect --format='{{ .GraphDriver.Data.MergedDir }}' <container_name>

For containers utilizing bind mounts or named volumes, locate the host-side source paths with:

docker inspect --format='{{range .Mounts}}{{.Type}}: {{.Source}} -> {{.Destination}}{{"\n"}}{{end}}' <container_name>

Practical demonstration:

# Launch a sample workload with volume attachment
docker run -d \
  --name demo-app \
  -v /opt/data:/app/data \
  -p 8080:80 \
  httpd:alpine

# Retrieve the container's root filesystem location
docker inspect --format='{{ .GraphDriver.Data.MergedDir }}' demo-app

# List volume mount mappings
docker inspect --format='{{range .Mounts}}Host: {{.Source}}, Container: {{.Destination}}{{end}}' demo-app

To examine the global volume storage directory:

docker volume inspect --format='{{ .Mountpoint }}' <volume_name>

This information assists in troubleshooting storage issues, performing manual backups of container data, or cleaning up orphaned layers when standard pruning commands prove insufficient.