How to: using nginx image
docker image inspect nginx | grep -A 40 ContainerConfig | less
docker image inspect nginx | grep -A 40 '"Config"' | less
docker image history nginx
docker tag nginx localhost/nginx:1.1
docker image ls
docker image history localhost/nginx:1.1 # tagging isn't a change
docker image rm $IMAGE_ID # error conflict
docker image rm localhost/nginx:1.1 # deleting removes tag
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