Run this:
### Everything below can be copy/pasted as a one-liner
. /etc/os-release && \
sudo apt update && \
sudo apt install -y apt-transport-https ca-certificates curl software-properties-common && \
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add - && \
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $VERSION_CODENAME stable" && \
sudo apt update && \
sudo apt install -y docker-ce docker-compose && \
# Verify it's running
sudo systemctl status docker
# Update (create if need be) the docker configuration to use the CGNAT CIDR range for container networking
sudo apt install -y moreutils jq && \
sudo bash -c 'if [ ! -f "/etc/docker/daemon.json" ] ; then echo "{}" > /etc/docker/daemon.json ; fi ; jq '\''."default-address-pools"[0].base = "100.64.0.0/16" | ."default-address-pools"[0].size = 24'\'' /etc/docker/daemon.json | sponge /etc/docker/daemon.json' ; cat /etc/docker/daemon.json
# Restart docker to pull in changes
sudo systemctl restart docker
# Set up cron task to clean up stale, unused docker images
sudo bash -c 'cat << EOF > /etc/cron.daily/docker-image-prune.cron.sh
#!/bin/bash
### Prune images older than 7 days
docker image prune -af --filter "until=$((7*24))h" 2> /dev/null > /dev/null
EOF
'
sudo chmod u+x /etc/cron.daily/docker-image-prune.cron.sh
