@@ -31,24 +31,24 @@ pages:

 # Installation:

 - ['installation/index.md', '**HIDDEN**']

-- ['installation/mac.md', 'Installation', 'Mac OS X']

 - ['installation/ubuntulinux.md', 'Installation', 'Ubuntu']

-- ['installation/rhel.md', 'Installation', 'Red Hat Enterprise Linux']

-- ['installation/oracle.md', 'Installation', 'Oracle Linux']

+- ['installation/mac.md', 'Installation', 'Mac OS X']

+- ['installation/windows.md', 'Installation', 'Microsoft Windows']

+- ['installation/amazon.md', 'Installation', 'Amazon EC2']

+- ['installation/archlinux.md', 'Installation', 'Arch Linux']

+- ['installation/binaries.md', 'Installation', 'Binaries']

 - ['installation/centos.md', 'Installation', 'CentOS']

+- ['installation/cruxlinux.md', 'Installation', 'CRUX Linux']

 - ['installation/debian.md', 'Installation', 'Debian']

-- ['installation/gentoolinux.md', 'Installation', 'Gentoo']

+- ['installation/fedora.md', 'Installation', 'Fedora']

+- ['installation/frugalware.md', 'Installation', 'FrugalWare']

 - ['installation/google.md', 'Installation', 'Google Cloud Platform']

-- ['installation/rackspace.md', 'Installation', 'Rackspace Cloud']

-- ['installation/amazon.md', 'Installation', 'Amazon EC2']

+- ['installation/gentoolinux.md', 'Installation', 'Gentoo']

 - ['installation/softlayer.md', 'Installation', 'IBM Softlayer']

-- ['installation/archlinux.md', 'Installation', 'Arch Linux']

-- ['installation/frugalware.md', 'Installation', 'FrugalWare']

-- ['installation/fedora.md', 'Installation', 'Fedora']

+- ['installation/rackspace.md', 'Installation', 'Rackspace Cloud']

+- ['installation/rhel.md', 'Installation', 'Red Hat Enterprise Linux']

+- ['installation/oracle.md', 'Installation', 'Oracle Linux']

 - ['installation/SUSE.md', 'Installation', 'SUSE']

-- ['installation/cruxlinux.md', 'Installation', 'CRUX Linux']

-- ['installation/windows.md', 'Installation', 'Microsoft Windows']

-- ['installation/binaries.md', 'Installation', 'Binaries']

 - ['compose/install.md', 'Installation', 'Docker Compose']

 # User Guide:

@@ -187,3 +187,4 @@ pages:

 - ['project/get-help.md', 'Contributor Guide', 'Where to get help']

 - ['project/coding-style.md', 'Contributor Guide', 'Coding style guide']

 - ['project/doc-style.md', 'Contributor Guide', 'Documentation style guide']

+

@@ -1,395 +1,305 @@

-page_title: Installation on Ubuntu

-page_description: Instructions for installing Docker on Ubuntu.

+page_title: Installation on Ubuntu 

+page_description: Instructions for installing Docker on Ubuntu. 

 page_keywords: Docker, Docker documentation, requirements, virtualbox, installation, ubuntu

-# Ubuntu

+#Ubuntu

-Docker is supported on the following versions of Ubuntu:

+Docker is supported on these Ubuntu operating systems:

- - [*Ubuntu Trusty 14.04 (LTS) (64-bit)*](#ubuntu-trusty-1404-lts-64-bit)

- - [*Ubuntu Precise 12.04 (LTS) (64-bit)*](#ubuntu-precise-1204-lts-64-bit)

- - [*Ubuntu Raring 13.04 and Saucy 13.10 (64

-   bit)*](#ubuntu-raring-1304-and-saucy-1310-64-bit)

+- Ubuntu Trusty 14.04 (LTS) 

+- Ubuntu Precise 12.04 (LTS) 

+- Ubuntu Saucy 13.10

-Please read [*Docker and UFW*](#docker-and-ufw), if you plan to use [UFW

-(Uncomplicated Firewall)](https://help.ubuntu.com/community/UFW)

+This page instructs you to install using Docker-managed release packages and

+installation mechanisms. Using these packages ensures you get the latest release

+of Docker. If you wish to install using Ubuntu-managed packages, consult your

+Ubuntu documentation.

-## Ubuntu Trusty 14.04 (LTS) (64-bit)

+##Prerequisites

-Ubuntu Trusty comes with a 3.13.0 Linux kernel, and a `docker.io` package which

-installs Docker 1.0.1 and all its prerequisites from Ubuntu's repository.

+Docker requires a 64-bit installation regardless of your Ubuntu version.

+Additionally, your kernel must be 3.10 at minimum. The latest 3.10 minor version

+or a newer maintained version are also acceptable.

-> **Note**:

-> Ubuntu (and Debian) contain a much older KDE3/GNOME2 package called ``docker``, so the

-> Ubuntu-maintained package and executable are named ``docker.io``.

+Kernels older than 3.10 lack some of the features required to run Docker

+containers. These older versions are known to have bugs which cause data loss

+and frequently panic under certain conditions.

-### Ubuntu-maintained Package Installation

+To check your current kernel version, open a terminal and use `uname -r` to display

+your kernel version:

-To install the latest Ubuntu package (this is **not** the most recent Docker release):

+	$ uname -r 

+	3.11.0-15-generic

-    $ sudo apt-get update

-    $ sudo apt-get install docker.io

+>**Caution** Some Ubuntu OS versions **require a version higher than 3.10** to

+>run Docker, see the prerequisites on this page that apply to your Ubuntu

+>version.

-Then, to enable tab-completion of Docker commands in BASH, either restart BASH or:

+###For Trusty 14.04

-    $ source /etc/bash_completion.d/docker*

+There are no prerequisites for this version.

-> **Note**:

-> Since the Ubuntu package is quite dated at this point, you may want to use

-> the following section to install the most recent release of Docker.

-> If you install the Docker version, you do not need to install ``docker.io`` from Ubuntu.

+###For Precise 12.04 (LTS)

-### Docker-maintained Package Installation

+For Ubuntu Precise, Docker requires the 3.13 kernel version. If your kernel

+version is older than 3.13, you must upgrade it. Refer to this table to see

+which packages are required for your environment:

-If you'd like to try the latest version of Docker:

+<style type="text/css"> .tg  {border-collapse:collapse;border-spacing:0;} .tg

+td{font-size:14px;padding:10px

+5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;}

+.tg-031{width:275px;font-family:monospace} </style> <table class="tg"> <tr> <td

+class="tg-031">linux-image-generic-lts-trusty</td> <td class="tg-031e">Generic

+Linux kernel image. This kernel has AUFS built in. This is required to run

+Docker.</td> </tr> <tr> <td class="tg-031">linux-headers-generic-lts-trusty</td>

+<td class="tg-031e">Allows packages such as ZFS and VirtualBox guest additions

+which depend on them. If you didn't install the headers for your existing

+kernel, then you can skip these headers for the"trusty" kernel. If you're

+unsure, you should include this package for safety.</td> </tr> <tr> <td

+class="tg-031">xserver-xorg-lts-trusty</td> <td class="tg-031e"

+rowspan="2">Optional in non-graphical environments without Unity/Xorg.

+<i>Required</i> when running Docker on machine with a graphical environment.

-First, check that your APT system can deal with `https`

-URLs: the file `/usr/lib/apt/methods/https`

-should exist. If it doesn't, you need to install the package

-`apt-transport-https`.

+<p>To learn more about the reasons for these packages, read the installation

+instructions for backported kernels, specifically the <a

+href="https://wiki.ubuntu.com/Kernel/LTSEnablementStack" target="_blank">LTS

+Enablement Stack</a> &mdash; refer to note 5 under each version.</p></td> </tr>

+<tr> <td class="tg-031">libgl1-mesa-glx-lts-trusty</td> </tr> </table> &nbsp;

-    [ -e /usr/lib/apt/methods/https ] || {

-      apt-get update

-      apt-get install apt-transport-https

-    }

+To upgrade your kernel and install the additional packages, do the following:

-Then, add the Docker repository key to your local keychain.

+1. Open a terminal on your Ubuntu host.

-    $ sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

+2. Update your package manager.

-Add the Docker repository to your apt sources list, update and install

-the `lxc-docker` package.

+		$ sudo apt-get update

-*You may receive a warning that the package isn't trusted. Answer yes to

-continue installation.*

+3. Install both the required and optional packages.

-    $ sudo sh -c "echo deb https://get.docker.com/ubuntu docker main\

-    > /etc/apt/sources.list.d/docker.list"

-    $ sudo apt-get update

-    $ sudo apt-get install lxc-docker

+		$ sudo apt-get install linux-image-generic-lts-trusty

-> **Note**:

->

-> There is also a simple `curl` script available to help with this process.

->

->     $ curl -sSL https://get.docker.com/ubuntu/ | sudo sh

+	Depending on your environment, you may install more as described in the preceding table.

-To verify that everything has worked as expected:

+4. Reboot your host.

-    $ sudo docker run -i -t ubuntu /bin/bash

+		$ sudo reboot

-Which should download the `ubuntu` image, and then start `bash` in a container.

+5. After your system reboots, go ahead and [install Docker](#installing-docker-on-ubuntu).

-Type `exit` to exit

-**Done!**, continue with the [User Guide](/userguide/).

+###For Saucy 13.10 (64 bit)

+Docker uses AUFS as the default storage backend. If you don't have this

+prerequisite installed, Docker's installation process adds it.

-## Ubuntu Precise 12.04 (LTS) (64-bit)

+##Installing Docker on Ubuntu

-This installation path should work at all times.

+Make sure you have intalled the prerequisites for your Ubuntu version. Then,

+install Docker using the following:

-### Dependencies

+1. Log into your Ubuntu installation as a user with `sudo` privileges.

-**Linux kernel 3.13**

+2. Verify that you have `wget` installed.

-For Ubuntu Precise, the currently recommended kernel version is 3.13.

-Ubuntu Precise installations with older kernels must be upgraded. The

-kernel you'll install when following these steps has AUFS built in.

-We also include the generic headers to enable packages that depend on them,

-like ZFS and the VirtualBox guest additions. If you didn't install the

-headers for your "precise" kernel, then you can skip these headers for the

-"trusty" kernel. If you're unsure, you should include the headers for safety.

+		$ which wget

-> **Warning**:

-> Kernels 3.8 and 3.11 are no longer supported by Canonical. Systems

-> running these kernels need to be updated using the instructions below.

-> Running Docker on these unsupported systems isn't supported either.

-> These old kernels are no longer patched for security vulnerabilities

-> and severe bugs which lead to data loss.

+	 If `wget` isn't installed, install it after updating your manager:

-Please read the installation instructions for backported kernels at

-Ubuntu.org to understand why you also need to install the Xorg packages

-when running Docker on a machine with a graphical environment like Unity.

-[LTS Enablement Stack](https://wiki.ubuntu.com/Kernel/LTSEnablementStack) refer to note 5 under

-each version.

+		$ sudo apt-get update $ sudo apt-get install wget

-    # install the backported kernel

-    $ sudo apt-get update

-    $ sudo apt-get install linux-image-generic-lts-trusty linux-headers-generic-lts-trusty

-    

-    # install the backported kernel and xorg if using Unity/Xorg

-    $ sudo apt-get install --install-recommends linux-generic-lts-trusty xserver-xorg-lts-trusty libgl1-mesa-glx-lts-trusty

+3. Get the latest Docker package.

-    # reboot

-    $ sudo reboot

+		$ wget -qO- https://get.docker.com/ | sh

-### Installation

+	 The system prompts you for your `sudo` password. Then, it downloads and

+	 installs Docker and its dependencies.

-> **Warning**: 

-> These instructions have changed for 0.6. If you are upgrading from an

-> earlier version, you will need to follow them again.

+4. Verify `docker` is installed correctly.

-Docker is available as a Debian package, which makes installation easy.

-**See the** [*Mirrors*](#mirrors) **section below if you are not

-in the United States.** Other sources of the Debian packages may be

-faster for you to install.

+		$ sudo docker run hello-world

-First, check that your APT system can deal with `https`

-URLs: the file `/usr/lib/apt/methods/https`

-should exist. If it doesn't, you need to install the package

-`apt-transport-https`.

+	This command downloads a test image and runs it in a container.

-    [ -e /usr/lib/apt/methods/https ] || {

-      apt-get update

-      apt-get install apt-transport-https

-    }

+## Optional Configurations for Docker on Ubuntu 

-Then, add the Docker repository key to your local keychain.

+This section contains optional procedures for configuring your Ubuntu to work

+better with Docker.

-    $ sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

+* [Create a docker group](#create-a-docker-group) 

+* [Adjust memory and swap accounting](#adjust-memory-and-swap-accounting) 

+* [Enable UFW forwarding](#enable-ufw-forwarding) 

+* [Configure a DNS server for use by Docker](#configure-a-dns-server-for-docker)

-Add the Docker repository to your apt sources list, update and install

-the `lxc-docker` package.

+### Create a docker group		

-*You may receive a warning that the package isn't trusted. Answer yes to

-continue installation.*

+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 other users can access it with

+`sudo`. For this reason, `docker` daemon always runs as the `root` user.

-    $ sudo sh -c "echo deb https://get.docker.com/ubuntu docker main\

-    > /etc/apt/sources.list.d/docker.list"

-    $ sudo apt-get update

-    $ sudo apt-get install lxc-docker

+To avoid having to use `sudo` when you use the `docker` command, create a Unix

+group called `docker` and add users to it. When the `docker` daemon starts, it

+makes the ownership of the Unix socket read/writable by the `docker` group.

-> **Note**:

-> 

-> There is also a simple `curl` script available to help with this process.

-> 

->     $ curl -sSL https://get.docker.com/ubuntu/ | sudo sh

+>**Warning**: The `docker` group is equivalent to the `root` user; For details

+>on how this impacts security in your system, see [*Docker Daemon Attack

+>Surface*](/articles/security/#docker-daemon-attack-surface) for details.

-Now verify that the installation has worked by downloading the

-`ubuntu` image and launching a container.

+To create the `docker` group and add your user:

-    $ sudo docker run -i -t ubuntu /bin/bash

+1. Log into Ubuntu as a user with `sudo` privileges.

-Type `exit` to exit

+	 This procedure assumes you log in as the `ubuntu` user.

-**Done!**, continue with the [User Guide](/userguide/).

+3. Create the `docker` group and add your user.

-## Ubuntu Raring 13.04 and Saucy 13.10 (64 bit)

+		$ sudo usermod -aG docker ubuntu

-These instructions cover both Ubuntu Raring 13.04 and Saucy 13.10.

+3. Log out and log back in.

-### Dependencies

+	This ensures your user is running with the correct permissions.

-**Optional AUFS filesystem support**

+4. Verify your work by running `docker` without `sudo`.

-Ubuntu Raring already comes with the 3.8 kernel, so we don't need to

-install it. However, not all systems have AUFS filesystem support

-enabled. AUFS support is optional as of version 0.7, but it's still

-available as a driver and we recommend using it if you can.

+		$ docker run hello-world

-To make sure AUFS is installed, run the following commands:

-    $ sudo apt-get update

-    $ sudo apt-get install linux-image-extra-`uname -r`

+### Adjust memory and swap accounting

-### Installation

+When users run Docker, they may see these messages when working with an image:

-Docker is available as a Debian package, which makes installation easy.

+    WARNING: Your kernel does not support cgroup swap limit. WARNING: Your

+    kernel does not support swap limit capabilities. Limitation discarded.

-> **Warning**: 

-> Please note that these instructions have changed for 0.6. If you are

-> upgrading from an earlier version, you will need to follow them again.

+To prevent these messages, enable memory and swap accounting on your system. To

+enable these on system using GNU GRUB (GNU GRand Unified Bootloader), do the

+following.

-First add the Docker repository key to your local keychain.

+1. Log into Ubuntu as a user with `sudo` privileges.

-    $ sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

+2. Edit the `/etc/default/grub` file.

-Add the Docker repository to your apt sources list, update and install

-the `lxc-docker` package.

+3. Set the `GRUB_CMDLINE_LINUX` value as follows:

-    $ sudo sh -c "echo deb http://get.docker.com/ubuntu docker main\

-    > /etc/apt/sources.list.d/docker.list"

-    $ sudo apt-get update

-    $ sudo apt-get install lxc-docker

+    	GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"

-Now verify that the installation has worked by downloading the

-`ubuntu` image and launching a container.

+4. Save and close the file.

-    $ sudo docker run -i -t ubuntu /bin/bash

+5. Update GRUB.

-Type `exit` to exit

+		$ sudo update-grub

-**Done!**, now continue with the [User Guide](/userguide/).

+6. Reboot your system.

-### Upgrade

-To install the latest version of Docker, use the standard

-`apt-get` method:

+### Enable UFW forwarding

-    # update your sources list

-    $ sudo apt-get update

+If you use [UFW (Uncomplicated Firewall)](https://help.ubuntu.com/community/UFW)

+on the same host as you run Docker, you'll need to do additional configuration.

+Docker uses a bridge to manage container networking. By default, UFW drops all

+forwarding traffic. As a result, for Docker to run when UFW is

+enabled, you must set UFW's forwarding policy appropriately.

-    # install the latest

-    $ sudo apt-get install lxc-docker

+Also, UFW's default set of rules denies all incoming traffic. If you want to be able

+to reach your containers from another host then you should also allow incoming

+connections on the Docker port (default `2375`).

-## Giving non-root access

+To configure UFW and allow incoming connections on the Docker port:

-The `docker` daemon always runs as the `root` user, and since Docker

-version 0.5.2, 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`.

+1. Log into Ubuntu as a user with `sudo` privileges.

-Starting in version 0.5.3, 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.

+2. Verify that UFW is installed and enabled.

-> **Warning**: 

-> The `docker` group (or the group specified with the `-G` flag) is

-> `root`-equivalent; see [*Docker Daemon Attack Surface*](

-> /articles/security/#docker-daemon-attack-surface) for details.

+		$ sudo ufw status

-**Example:**

+3. Open the `/etc/default/ufw` file for editing.

-    # Add the docker group if it doesn't already exist.

-    $ sudo groupadd docker

+		$ sudo nano /etc/default/ufw

-    # 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

+4. Set the `DEFAULT_FORWARD_POLICY` policy to:

-    # Restart the Docker daemon.

-    # If you are in Ubuntu 14.04, use docker.io instead of docker

-    $ sudo service docker restart

+    	DEFAULT_FORWARD_POLICY="ACCEPT"

-## Memory and Swap Accounting

+5. Save and close the file.

-If you want to enable memory and swap accounting, you must add the

-following command-line parameters to your kernel:

+6. Reload UFW to use the new setting.

-    cgroup_enable=memory swapaccount=1

+		$ sudo ufw reload

-On systems using GRUB (which is the default for Ubuntu), you can add

-those parameters by editing `/etc/default/grub` and

-extending `GRUB_CMDLINE_LINUX`. Look for the

-following line:

+7. Allow incoming connections on the Docker port.

-    GRUB_CMDLINE_LINUX=""

+		$ sudo ufw allow 2375/tcp

-And replace it by the following one:

+### Configure a DNS server for use by Docker

-    GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"

+Systems that run Ubuntu or an Ubuntu derivative on the desktop typically use

+`127.0.0.1` as the default `nameserver` in `/etc/resolv.conf` file. The

+NetworkManager also sets up `dnsmasq` to use the real DNS servers of the

+connection and sets up `nameserver 127.0.0.1` in /`etc/resolv.conf`.

-Then run `sudo update-grub`, and reboot.

+When starting containers on desktop machines with these configurations, Docker

+users see this warning:

-These parameters will help you get rid of the following warnings:

+    WARNING: Local (127.0.0.1) DNS resolver found in resolv.conf and containers

+    can't use it. Using default external servers : [8.8.8.8 8.8.4.4]

-    WARNING: Your kernel does not support cgroup swap limit.

-    WARNING: Your kernel does not support swap limit capabilities. Limitation discarded.

+The warning occurs because Docker containers can't use the local DNS nameserver.

+Instead, Docker defaults to using an external nameserver.

-## Troubleshooting

+To avoid this warning, you can specify a DNS server for use by Docker

+containers. Or, you can disable `dnsmasq` in NetworkManager. Though, disabiling

+`dnsmasq` might make DNS resolution slower on some networks.

-On Linux Mint, the `cgroup-lite` and `apparmor` packages are not

-installed by default. Before Docker will work correctly, you will need

-to install this via:

+To specify a DNS server for use by Docker:

-    $ sudo apt-get update && sudo apt-get install cgroup-lite apparmor

+1. Log into Ubuntu as a user with `sudo` privileges.

-## Docker and UFW

+2. Open the `/etc/default/docker` file for editing.

-Docker uses a bridge to manage container networking. By default, UFW

-drops all forwarding traffic. As a result you will need to enable UFW

-forwarding:

+     	$ sudo nano /etc/default/docker

-    $ sudo nano /etc/default/ufw

+3. Add a setting for Docker.

-    # Change:

-    # DEFAULT_FORWARD_POLICY="DROP"

-    # to

-    DEFAULT_FORWARD_POLICY="ACCEPT"

+      	DOCKER_OPTS="--dns 8.8.8.8"

-Then reload UFW:

+    Replace `8.8.8.8` with a local DNS server such as `192.168.1.1`. You can also

+    specify multiple DNS servers. Separated them with spaces, for example:

-    $ sudo ufw reload

+      	--dns 8.8.8.8 --dns 192.168.1.1

-UFW's default set of rules denies all incoming traffic. If you want to

-be able to reach your containers from another host then you should allow

-incoming connections on the Docker port (default 2375):

+	>**Warning**: If you're doing this on a laptop which connects to various

+	>networks, make sure to choose a public DNS server.

-    $ sudo ufw allow 2375/tcp

+4. Save and close the file.

-## Docker and local DNS server warnings

+5. Restart the Docker daemon.

-Systems which are running Ubuntu or an Ubuntu derivative on the desktop

-will use 127.0.0.1 as the default nameserver in /etc/resolv.conf.

-NetworkManager sets up dnsmasq to use the real DNS servers of the

-connection and sets up nameserver 127.0.0.1 in /etc/resolv.conf.

+    	$ sudo restart docker

-When starting containers on these desktop machines, users will see a

-warning:

-    WARNING: Local (127.0.0.1) DNS resolver found in resolv.conf and containers can't use it. Using default external servers : [8.8.8.8 8.8.4.4]

+ 

+ 

-This warning is shown because the containers can't use the local DNS

-nameserver and Docker will default to using an external nameserver.

+**Or, as an alternative to the previous procedure,** disable `dnsmasq` in

+NetworkManager (this might slow your network).

-This can be worked around by specifying a DNS server to be used by the

-Docker daemon for the containers:

+1. Open the `/etc/default/docker` file for editing.

-    $ sudo nano /etc/default/docker

-    ---

-    # Add:

-    DOCKER_OPTS="--dns 8.8.8.8"

-    # 8.8.8.8 could be replaced with a local DNS server, such as 192.168.1.1

-    # multiple DNS servers can be specified: --dns 8.8.8.8 --dns 192.168.1.1

+		$ sudo nano /etc/NetworkManager/NetworkManager.conf

-The Docker daemon has to be restarted:

+2. Comment out the `dns=dsnmasq` line:

-    $ sudo restart docker

+		dns=dnsmasq

-> **Warning**: 

-> If you're doing this on a laptop which connects to various networks,

-> make sure to choose a public DNS server.

+3. Save and close the file.

-An alternative solution involves disabling dnsmasq in NetworkManager by

-following these steps:

+4. Restart both the NetworkManager and Docker.

-    $ sudo nano /etc/NetworkManager/NetworkManager.conf

-    ----

-    # Change:

-    dns=dnsmasq

-    # to

-    #dns=dnsmasq

+		$ sudo restart network-manager $ sudo restart docker

-NetworkManager and Docker need to be restarted afterwards:

-    $ sudo restart network-manager

-    $ sudo restart docker

+## Upgrade Docker

-> **Warning**: This might make DNS resolution slower on some networks.

+To install the latest version of Docker, use the standard `-N` flag with `wget`:

-## Mirrors

+	$ wget -N https://get.docker.com/ | sh

-You should `ping get.docker.com` and compare the

-latency to the following mirrors, and pick whichever one is best for

-you.

-

-### Yandex

-

-[Yandex](http://yandex.ru/) in Russia is mirroring the Docker Debian

-packages, updating every 6 hours.

-Substitute `http://mirror.yandex.ru/mirrors/docker/` for

-`http://get.docker.com/ubuntu` in the instructions above.

-For example:

-

-    $ sudo sh -c "echo deb http://mirror.yandex.ru/mirrors/docker/ docker main\

-    > /etc/apt/sources.list.d/docker.list"

-    $ sudo apt-get update

-    $ sudo apt-get install lxc-docker