How do run Docker on Debian

This is about how to run Docker on Debian Linux, not why you should want to. But it deserves an answer.

Supposing you’re running FreeBSD and someone really, really, really wants to you run something that’s only available as a Docker container? The only practical way is on a Linux VM running under bhyve. RHEL is expensive (and I no longer have an employer willing to stand me a developers’ license), CentoOS is no more. If you want to stay mainstream that leaves Debian and Arch. In my experience, Debian runs easily enough under bhyve, so Debian it is.

So log in to your new Debian installation as root and run the following, which took a while to work out so this is really a cheat sheet…

apt update
apt install curl ca-certificates

# Get docker GPG key
curl -fsSL https://download.docker.com/linux/debian/gpg \
   -o /etc/apt/keyrings/docker.asc

# This adds the latest Docker repo info to your APT sources list
echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc]   https://download.docker.com/linux/debian $(. /etc/os-release && echo "$VERSION_CODENAME") stable" \
   | tee /etc/apt/sources.list.d/docker.list > /dev/null
apt update

# Finally install Docker
apt install docker-ce docker-ce-cli containerd.io -y

# You can check it's there by running   docker --version

systemctl enable docker

You can check it’s running with systemctl stop docker, and stop it with systemctl stop docker.

If you’re going to run this as a non-root user (probably a good idea) you’ll probably need to add yourself to the docker group:

usermod -aG docker your-user-id

This is just the Linux way of adding you to the /etc/group file.