Kernel Requirements
===================
If you want to have a full working CRUX+Docker system you will need to
rebuild your kernel and enable various networking, cgroups
and optional lvm options
You may check your kernel configuration by running:
::
/usr/share/docker/check-config.sh
.. note:: If you receive an error such as "cgroup hierarchy: nonexistent??"
then you should run ``cgroupfs-mount`` and re-run
``/usr/share/docker/check-config.sh``.
Please follow the guideance of the output of
``/usr/share/docker/check-config.sh`` carefully.
Execution Engines
=================
As of Docker 0.9+ execution engines are pluggable and as such Docker
no longer depends on lxc.
The new default execution driver is now an internal ``libcontainer``
driver that replaces the need for lxc.
Please see the `Docker Documentation <http://docs.docker.io>`_
if you want to use a different execution engine other then the default.
Storage Backends
================
Docker comes with three main Storage Backends:
- AUFS (*requires AUFS kernel/patches*)
- devmapper
- btrfs
It is recommended you use the devmapper or btrfs backend (Default: devmapper).
To use the ``btrfs`` backend edit ``/etc/docker.conf``
and modify the ``DOCKER_OPTS`` with:
::
DOCKER_OPTS="-s btrfs"
.. note:: As of Docker 0.10.x the ``btrfs`` storage backend is now
considered stable and has been promoted to an officially
supported storage backend.
Docker Client
=============
Add yourself to the ``docker`` group if you wish to access
the Docker daemon on localhost via UNIX Socket.
