docker_for_rpi

Just built a kernel to enable docker to run on the Raspberry Pi Model 2 I have stored this in the rpi2_linux directory. The linux directory is for the prvious models and is an earlier version.

NOTE: Due to a recent kernel update if docker stops working after you have run apt-get update you will need to install the new kernel & modules I have updated in the repository. I raised and closed an issue on this. Please note that I can't guarantee to keep updating kernels into the future, but the blog links below explain how to do this and following them didn't take me very long this time.

Docker for Raspberry Pi

Using this repository to store useful files to get the docker programme to run on a Raspberry Pi using the Raspbian debian Wheezy distribution.

DISCLAIMER: warranties, whether express or implied, including, without limitation, any implied warranties or fitness for a particular purpose are not provided. Use of anything in this repository is entirely at your own risk.

I wrote a blog which pulled together existing blogs which explain how I produced the rasbian kernel for docker: http://stevef1uk.blogspot.co.uk/2014/06/how-to-run-docker-on-raspberry-pi.html

I also wrote one on how to cross compile the linux kernel for the RPI from a Mac: http://stevef1uk.blogspot.co.uk/2014/06/here-be-dragons-how-to-cross-compile.html

Feel free to do this yourself, or if you doen't have the time/patience then I have uploaded the linux kernel which contains LXC and AUFS.

1. linux/kerrnel.img - backup your old /boot/kernel.img on your RPI and copy this one into /boot

2. modules.tar - extract this is the directory /lib/modules

3. reboot

4. Now install lxc

$sudo su
$mkdir /opt/lxc
$cd /opt/lxc
$git clone https://github.com/lxc/lxc.git
$apt-get install automake libcap-dev
$cd lxc
$./autogen.sh && ./configure && make && make install

Now to check that LXC is working correctly on the RPi type:

$lxc-checkconfig

The steps below are my notes on how to build docker on a raspberry Pi to get the very latest release. The resin.io guys stopped at 0.8: https://github.com/resin-io/lxc-docker-PKGBUILD/releases

If you don't need the very latest docker than download the 0.8 release and untar it to the root partition.

5. As root and from / tar xvf docker-1.2.0-armv6h.pkg.tar

6. I have provided an example start_docker script to set the LD_LIBRARY_PATH which docker needs.

I encountered the following error when trying to run an image: Error: Cannot start container fe60acdc3c0ef5ab84f5ce506c1358ff37af69a2a60444a8cf4231165b6cbd2a: mkdir /sys/fs/devices: no such file or directory

The following link helped me fix this: https://github.com/ubergarm/debian-docker-runit

Stop your old docker daeamon

Remove cgroup mount point from /etc/fstab if you have it e.g. cgroup /sys/fs/cgroup cgroup defaults 0 0

$sudo umount /sys/fs/cgroup

You may need to apt-get remove systemd You may need to reboot.

Install runit and cgroupfs-mount script

This will start the docker daemon up and running and it will come back after reboots.

$sudo -i
$apt-get install runit
$cd /usr/local/bin 
$wget https://raw.github.com/tianon/cgroupfs-mount/master/cgroupfs-mount
$chmod a+x cgroupfs-mount
$cd /etc/sv
$git clone https://github.com/ubergarm/debian-docker-runit
$ln -s /etc/sv/debian-docker-runit/docker /etc/service/docker

More commands

$man sv
$sv status docker
$sv stop docker
$sv start docker

I noticed that the CPU was running a little high at idle so I added the line:

cgroup_disable=memory

to the file /boot/config.txt to resolve this.

The steps below summarise what I did to build docker from the latest source code.

1. Once downloaded the docker source I made some changes to the Dockerfile, which I have included in the docker directory.

2. Need to edit a number of docker go files to change amd64 to arm I used: find . -name "*.go" -print -exec grep amd64 {} ; | less

Then: perl -p -i -e "s/amd64/arm/g" *.go

For docker 1.9 I needed to delete the file vendor/src/github.com/opencontainers/runc/libcontainer/system/syscall_linux_64.go owing to the error 'Setgid redeclared in this block'

3. In the docker directory and with docker running type sudo make