moby--moby/docs/installation/debian.md

Debian

Docker is supported on the following versions of Debian:

• Debian 8.0 Jessie (64-bit)
• Debian 7.7 Wheezy (64-bit)

Debian Jessie 8.0 (64-bit)

Debian 8 comes with a 3.16.0 Linux kernel, the docker.io package can be found in the jessie-backports repository. Reasoning behind this can be found here. Instructions how to enable the backports repository can be found here.

Note

: Debian contains a much older KDE3/GNOME2 package called docker, so the package and the executable are called docker.io.

Installation

Make sure you enabled the jessie-backports repository, as stated above.

To install the latest Debian package (may not be the latest Docker release):

$ sudo apt-get update
$ sudo apt-get install docker.io

To verify that everything has worked as expected:

$ sudo docker run --rm hello-world

This command downloads and runs the hello-world image in a container. When the container runs, it prints an informational message. Then, it exits.

Note

: If you want to enable memory and swap accounting see this.

Uninstallation

To uninstall the Docker package:

$ sudo apt-get purge docker-io

To uninstall the Docker package and dependencies that are no longer needed:

$ sudo apt-get autoremove --purge docker-io

The above commands will not remove images, containers, volumes, or user created configuration files on your host. If you wish to delete all images, containers, and volumes run the following command:

$ rm -rf /var/lib/docker

You must delete the user created configuration files manually.

Debian Wheezy/Stable 7.x (64-bit)

Docker requires Kernel 3.8+, while Wheezy ships with Kernel 3.2 (for more details on why 3.8 is required, see discussion on bug #407).

Fortunately, wheezy-backports currently has Kernel 3.16 , which is officially supported by Docker.

Installation

1. Install Kernel from wheezy-backports

   Add the following line to your /etc/apt/sources.list

   deb http://http.debian.net/debian wheezy-backports main

   then install the linux-image-amd64 package (note the use of -t wheezy-backports)

    $ sudo apt-get update
    $ sudo apt-get install -t wheezy-backports linux-image-amd64
   

2. Restart your system. This is necessary for Debian to use your new kernel.

3. Install Docker using the get.docker.com script:

   curl -sSL https://get.docker.com/ | sh

Note

: If your company is behind a filtering proxy, you may find that the apt-key command fails for the Docker repo during installation. To work around this, add the key directly using the following:

  $ wget -qO- https://get.docker.com/gpg | sudo apt-key add -

Uninstallation

To uninstall the Docker package:

$ sudo apt-get purge lxc-docker

To uninstall the Docker package and dependencies that are no longer needed:

$ sudo apt-get autoremove --purge lxc-docker

The above commands will not remove images, containers, volumes, or user created configuration files on your host. If you wish to delete all images, containers, and volumes run the following command:

$ rm -rf /var/lib/docker

You must delete the user created configuration files manually.

Giving non-root access

The docker daemon always runs as the root user and the docker daemon binds to a Unix socket instead of a TCP port. By default that Unix socket is owned by the user root, and so, by default, you can access it with sudo.

If you (or your Docker installer) create a Unix group called docker and add users to it, then the docker daemon will make the ownership of the Unix socket read/writable by the docker group when the daemon starts. The docker daemon must always run as the root user, but if you run the docker client as a user in the docker group then you don't need to add sudo to all the client commands. From Docker 0.9.0 you can use the -G flag to specify an alternative group.

Warning

: The docker group (or the group specified with the -G flag) is root-equivalent; see Docker Daemon Attack Surface details.

Example:

# Add the docker group if it doesn't already exist.
$ sudo groupadd docker

# Add the connected user "${USER}" to the docker group.
# Change the user name to match your preferred user.
# You may have to logout and log back in again for
# this to take effect.
$ sudo gpasswd -a ${USER} docker

# Restart the Docker daemon.
$ sudo service docker restart

What next?

Continue with the User Guide.