# where are the images initially stored?
sudo docker info | grep "Root Dir"
# ... not where I want them
# modify the configuration files to change to image location
# NOTE this generates an error
# WARNING: Usage of loopback devices is strongly discouraged for production use.
# Use `--storage-opt dm.thinpooldev` to specify a custom block storage device.
# see https://.com/questions/31620825/
# warning-of-usage-of-loopback-devices-is-strongly-discouraged-for-production-use
sudo sed -i ' s@#DOCKER_OPTS=.*@DOCKER_OPTS="-g /home/ubuntu/kaggle/docker"@ ' /etc/default/docker
sudo chmod -R ugo+rw /lib/systemd/system/docker.service
sudo cp /lib/systemd/system/docker.service /etc/systemd/system/
sudo chmod -R ugo+rw /etc/systemd/system/
sudo sed -i ' s@ExecStart.*@ExecStart=/usr/bin/dockerd $DOCKER_OPTS -H fd://@ ' /etc/systemd/system/docker.service
sudo sed -i '/ExecStart/a EnvironmentFile=-/etc/default/docker' /etc/systemd/system/docker.service
sudo systemctl daemon-reload
sudo systemctl restart docker
sudo docker info | grep "Root Dir"
# now they're where I want them