boot2docker is a lightweight Linux distribution based on Tiny Core Linux made specifically to run Docker containers. It runs completely from RAM, weighs ~23MB and boots in ~5-6s (YMMV).
Head over to the Releases Page to grab the ISO.
Simply boot from the ISO, and you're done. It runs on VMs and bare-metal machines.
If you want your containers to persist accross reboots, just attach an ext4 formatted disk to your VM, and boot2docker will automount it on /var/lib/docker. It will also persist the SSH keys of the machine.
boot2docker auto logs in, but if you want to SSH into the machine, the credentials are:
login: docker
pass: tcuser
http://www.youtube.com/watch?v=QzfddDvNVv0
- Kernel 3.12.1 with AUFS
- Docker 0.7
- LXC 1.0-alpha2
- Container persistance via disk automount on
/var/lib/docker - SSH keys persistance via disk automount
boot2docker is built with Docker, via Dockerfiles.
It is composed in three disctinct steps:
base: fetches, patches with AUFS support and builds the 3.12.1 Linux Kernel with Tiny Core base configurationrootfs: builds the base rootfs for boot2docker (not complete)- running
rootfs: when you run this image, it will build the rootfs, download the latest Docker release and create the.isofile on/of the container. This way you can update Docker without having to completely rebuild everything.
So the build process goes like this:
$ sudo docker build -t boot2docker-base base/
$ sudo docker build -t boot2docker rootfs/
Once that's done, to build a custom boot2docker.iso, just run the built rootfs image:
$ sudo docker run --privileged boot2docker
<CONTAINER_ID>
$ sudo docker cp <CONTAINER_ID>:/boot2docker.iso .
Why not CoreOS?
I got asked that question a lot, so I thought I should put it here once and for all. I liked the original idea of CoreOS: the smallest possible way to boot to docker. Unfortunately CoreOS has been growing larger and just did too many things for me. I just wanted the fastest way to boot to Docker.