Inspect container state, copy files, check resource stats, and save/load images as tarballs.
Inspecting Containers
docker inspect mycontainer
docker inspect --format={{.State.Status}} mycontainer
docker inspect --format={{.NetworkSettings.IPAddress}} mycontainer
docker top mycontainer # running processes
docker stats mycontainer # resource usage
# Copy files to/from container
docker cp mycontainer:/app/error.log ./error.log
docker cp ./config.json mycontainer:/app/
# Save / load images
docker save myapp:1.0 | gzip > myapp.tar.gz
docker load < myapp.tar.gz