moby--moby/docs/sources/installation/gentoolinux.md

page_title: Installation on Gentoo
page_description: Installation instructions for Docker on Gentoo.
page_keywords: gentoo linux, virtualization, docker, documentation, installation

# Gentoo

Installing Docker on Gentoo Linux can be accomplished using one of two ways: the **official** way and the `docker-overlay` way.

Official project page of [Gentoo Docker](https://wiki.gentoo.org/wiki/Project:Docker) team.

## Official way
The first and recommended way if you are looking for a stable  
experience is to use the official `app-emulation/docker` package directly  
from the tree.

If any issues arise from this ebuild including, missing kernel 
configuration flags or dependencies, open a bug 
on the Gentoo [Bugzilla](https://bugs.gentoo.org) assigned to `docker AT gentoo DOT org` 
or join and ask in the official
[IRC](http://webchat.freenode.net?channels=%23gentoo-containers&uio=d4) channel on the Freenode network.

## docker-overlay way

If you're looking for a `-bin` ebuild, a live ebuild, or a bleeding edge
ebuild, use the provided overlay, [docker-overlay](https://github.com/tianon/docker-overlay)
which can be added using `app-portage/layman`. The most accurate and
up-to-date documentation for properly installing and using the overlay
can be found in the [overlay](https://github.com/tianon/docker-overlay/blob/master/README.md#using-this-overlay).

If any issues arise from this ebuild or the resulting binary, including
and especially missing kernel configuration flags or dependencies, 
open an [issue](https://github.com/tianon/docker-overlay/issues) on 
the `docker-overlay` repository or ping `tianon` directly in the `#docker` 
IRC channel on the Freenode network.

## Installation

### Available USE flags

| USE Flag      | Default | Description |
| ------------- |:-------:|:------------|
| aufs          |         |Enables dependencies for the "aufs" graph driver, including necessary kernel flags.|
| btrfs         |         |Enables dependencies for the "btrfs" graph driver, including necessary kernel flags.|
| contrib       |  Yes    |Install additional contributed scripts and components.|
| device-mapper |  Yes    |Enables dependencies for the "devicemapper" graph driver, including necessary kernel flags.|
| doc           |         |Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally.|
| lxc           |         |Enables dependencies for the "lxc" execution driver.|
| vim-syntax    |         |Pulls in related vim syntax scripts.|
| zsh-completion|         |Enable zsh completion support.|

USE flags are described in detail on [tianon's
blog](https://tianon.github.io/post/2014/05/17/docker-on-gentoo.html).

The package should properly pull in all the necessary dependencies and
prompt for all necessary kernel options.

    $ sudo emerge -av app-emulation/docker

>Note: Sometimes there is a disparity between the latest versions 
>in the official **Gentoo tree** and the **docker-overlay**.  
>Please be patient, and the latest version should propagate shortly.

## Starting Docker

Ensure that you are running a kernel that includes all the necessary
modules and configuration (and optionally for device-mapper
and AUFS or Btrfs, depending on the storage driver you've decided to use).

To use Docker, the `docker` daemon must be running as **root**.  
To use Docker as a **non-root** user, add yourself to the **docker** 
group by running the following command:

    $ sudo usermod -a -G docker user
 
### OpenRC

To start the `docker` daemon:

    $ sudo /etc/init.d/docker start

To start on system boot:

    $ sudo rc-update add docker default

### systemd

To start the `docker` daemon:

    $ sudo systemctl start docker

To start on system boot:

    $ sudo systemctl enable docker