Mac OS X Install Docker

Mac OS X

Note: This release of Docker deprecates the Boot2Docker command line in favor of Docker Machine. Use the Docker Toolbox to install Docker Machine as well as the other Docker tools.

You install Docker using Docker Toolbox. Docker Toolbox includes the following Docker tools:

• Docker Machine for running the docker-machine binary
• Docker Engine for running the docker binary
• Docker Compose for running the docker-compose binary
• Kitematic, the Docker GUI
• a shell preconfigured for a Docker command-line environment
• Oracle VM VirtualBox

Because the Docker daemon uses Linux-specific kernel features, you can’t run Docker natively in OS X. Instead, you must use docker-machine to create and attach to a virtual machine (VM). This machine is a Linux VM that hosts Docker for you on your Mac.

Requirements

Your Mac must be running OS X 10.8 “Mountain Lion” or newer to install the Docker Toolbox.

Learn the key concepts before installing

In a Docker installation on Linux, your physical machine is both the localhost and the Docker host. In networking, localhost means your computer. The Docker host is the computer on which the containers run.

On a typical Linux installation, the Docker client, the Docker daemon, and any containers run directly on your localhost. This means you can address ports on a Docker container using standard localhost addressing such as localhost:8000 or 0.0.0.0:8376.

In an OS X installation, the docker daemon is running inside a Linux VM called default. The default is a lightweight Linux VM made specifically to run the Docker daemon on Mac OS X. The VM runs completely from RAM, is a small ~24MB download, and boots in approximately 5s.

In OS X, the Docker host address is the address of the Linux VM. When you start the VM with docker-machine it is assigned an IP address. When you start a container, the ports on a container map to ports on the VM. To see this in practice, work through the exercises on this page.

Installation

If you have VirtualBox running, you must shut it down before running the installer.

1. Go to the Docker Toolbox page.

2. Click the installer link to download.

3. Install Docker Toolbox by double-clicking the package or by right-clicking and choosing “Open” from the pop-up menu.

   The installer launches the “Install Docker Toolbox” dialog.

   

4. Press “Continue” to install the toolbox.

   The installer presents you with options to customize the standard installation.

   

   By default, the standard Docker Toolbox installation:

   • installs binaries for the Docker tools in /usr/local/bin
   • makes these binaries available to all users
   • installs VirtualBox; or updates any existing installation

   Change these defaults by pressing “Customize” or “Change Install Location.”

5. Press “Install” to perform the standard installation.

   The system prompts you for your password.

   

6. Provide your password to continue with the installation.

   When it completes, the installer provides you with some information you can use to complete some common tasks.

   

7. Press “Close” to exit.

Running a Docker Container

To run a Docker container, you:

• create a new (or start an existing) Docker virtual machine
• switch your environment to your new VM
• use the docker client to create, load, and manage containers

Once you create a machine, you can reuse it as often as you like. Like any VirtualBox VM, it maintains its configuration between uses.

There are two ways to use the installed tools, from the Docker Quickstart Terminal or from your shell.

From the Docker Quickstart Terminal

1. Open the “Applications” folder or the “Launchpad”.

2. Find the Docker Quickstart Terminal and double-click to launch it.

   The application:

   • opens a terminal window
   • creates a default VM if it doesn’t exists, and starts the VM after
   • points the terminal environment to this VM

   Once the launch completes, the Docker Quickstart Terminal reports:

   

   Now, you can run docker commands.

3. Verify your setup succeeded by running the hello-worldcontainer.

   $ docker run hello-world
   Unable to find image 'hello-world:latest' locally
   511136ea3c5a: Pull complete
   31cbccb51277: Pull complete
   e45a5af57b00: Pull complete
   hello-world:latest: The image you are pulling has been verified.
   Important: image verification is a tech preview feature and should not be
   relied on to provide security.
   Status: Downloaded newer image for hello-world:latest
   Hello from Docker.
   This message shows that your installation appears to be working correctly.
   
   
   To generate this message, Docker took the following steps:
   1. The Docker client contacted the Docker daemon.
   2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
      (Assuming it was not already locally available.)
   3. The Docker daemon created a new container from that image which runs the
      executable that produces the output you are currently reading.
   4. The Docker daemon streamed that output to the Docker client, which sent it
      to your terminal.
   
   
   To try something more ambitious, you can run an Ubuntu container with:
   $ docker run -it ubuntu bash
   
   
   For more examples and ideas, visit:
   http://docs.docker.com/userguide/
   

A more typical way to interact with the Docker tools is from your regular shell command line.

From your shell

This section assumes you are running a Bash shell. You may be running a different shell such as C Shell but the commands are the same.

1. Create a new Docker VM.

   $ docker-machine create --driver virtualbox default
   Creating VirtualBox VM...
   Creating SSH key...
   Starting VirtualBox VM...
   Starting VM...
   To see how to connect Docker to this machine, run: docker-machine env default
   

   This creates a new default VM in VirtualBox.

   The command also creates a machine configuration in the~/.docker/machine/machines/default directory. You only need to run the create command once. Then, you can use docker-machine to start, stop, query, and otherwise manage the VM from the command line.

2. List your available machines.

   $ docker-machine ls
   NAME                ACTIVE   DRIVER       STATE     URL                         SWARM
   default             *        virtualbox   Running   tcp://192.168.99.101:2376
   

   If you have previously installed the deprecated Boot2Docker application or run the Docker Quickstart Terminal, you may have a dev VM as well. When you created default VM, the docker-machine command provided instructions for learning how to connect the VM.

3. Get the environment commands for your new VM.

   $ docker-machine env default
   export DOCKER_TLS_VERIFY="1"
   export DOCKER_HOST="tcp://192.168.99.101:2376"
   export DOCKER_CERT_PATH="/Users/mary/.docker/machine/machines/default"
   export DOCKER_MACHINE_NAME="default"
   # Run this command to configure your shell:
   # eval "$(docker-machine env default)"
   

4. Connect your shell to the default machine.

   $ eval "$(docker-machine env default)"
   

5. Run the hello-world container to verify your setup.

   $ docker run hello-world
   

Learn about your Toolbox installation

Toolbox installs the Docker Engine binary, the Docker binary on your system. When you use the Docker Quickstart Terminal or create a default VM manually, Docker Machine updates the ~/.docker/machine/machines/default folder to your system. This folder contains the configuration for the VM.

You can create multiple VMs on your system with Docker Machine. Therefore, you may end up with multiple VM folders if you have more than one VM. To remove a VM, use the docker-machine rm <machine-name> command.

Migrate from Boot2Docker

If you were using Boot2Docker previously, you have a pre-existing Docker boot2docker-vm VM on your local system. To allow Docker Machine to manage this older VM, you can migrate it.

1. Open a terminal or the Docker CLI on your system.

2. Type the following command.

   $ docker-machine create -d virtualbox --virtualbox-import-boot2docker-vm boot2docker-vm docker-vm
   

3. Use the docker-machine command to interact with the migrated VM.

The docker-machine subcommands are slightly different than the boot2docker subcommands. The table below lists the equivalent docker-machine subcommand and what it does:

boot2docker	docker-machine	docker-machine description
init	create	Creates a new docker host.
up	start	Starts a stopped machine.
ssh	ssh	Runs a command or interactive ssh session on the machine.
save	-	Not applicable.
down	stop	Stops a running machine.
poweroff	stop	Stops a running machine.
reset	restart	Restarts a running machine.
config	inspect	Prints machine configuration details.
status	ls	Lists all machines and their status.
info	inspect	Displays a machine’s details.
ip	ip	Displays the machine’s ip address.
shellinit	env	Displays shell commands needed to configure your shell to interact with a machine
delete	rm	Removes a machine.
download	-	Not applicable.
upgrade	upgrade	Upgrades a machine’s Docker client to the latest stable release.

Example of Docker on Mac OS X

Work through this section to try some practical container tasks on a VM. At this point, you should have a VM running and be connected to it through your shell. To verify this, run the following commands:

$ docker-machine ls
NAME                ACTIVE   DRIVER       STATE     URL                         SWARM
default             *        virtualbox   Running   tcp://192.168.99.100:2376

The ACTIVE machine, in this case default, is the one your environment is pointing to.

Access container ports

1. Start an NGINX container on the DOCKER_HOST.

   $ docker run -d -P --name web nginx
   

   Normally, the docker run commands starts a container, runs it, and then exits. The -d flag keeps the container running in the background after the docker run command completes. The -Pflag publishes exposed ports from the container to your local host; this lets you access them from your Mac.

2. Display your running container with docker ps command

   CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS              PORTS                                           NAMES
   5fb65ff765e9        nginx:latest        "nginx -g 'daemon of   3 minutes ago       Up 3 minutes        0.0.0.0:49156->443/tcp, 0.0.0.0:49157->80/tcp   web
   

   At this point, you can see nginx is running as a daemon.

3. View just the container’s ports.

   $ docker port web
   443/tcp -> 0.0.0.0:49156
   80/tcp -> 0.0.0.0:49157
   

   This tells you that the web container’s port 80 is mapped to port49157 on your Docker host.

4. Enter the http://localhost:49157 address (localhost is 0.0.0.0) in your browser:

   

   This didn’t work. The reason it doesn’t work is your DOCKER_HOST address is not the localhost address (0.0.0.0) but is instead the address of the your Docker VM.

5. Get the address of the default VM.

   $ docker-machine ip default
   192.168.59.103
   

6. Enter the http://192.168.59.103:49157 address in your browser:

   

   Success!

7. To stop and then remove your running nginx container, do the following:

   $ docker stop web
   $ docker rm web
   

Mount a volume on the container

When you start a container it automatically shares your /Users/username directory with the VM. You can use this share point to mount directories onto your container. The next exercise demonstrates how to do this.

1. Change to your user $HOME directory.

   $ cd $HOME
   

2. Make a new site directory.

   $ mkdir site
   

3. Change into the site directory.

   $ cd site
   

4. Create a new index.html file.

   $ echo "my new site" > index.html
   

5. Start a new nginx container and replace the html folder with your site directory.

   $ docker run -d -P -v $HOME/site:/usr/share/nginx/html \
     --name mysite nginx
   

6. Get the mysite container’s port.

   $ docker port mysite
   80/tcp -> 0.0.0.0:49166
   443/tcp -> 0.0.0.0:49165
   

7. Open the site in a browser:

   

8. Try adding a page to your $HOME/site in real time.

   $ echo "This is cool" > cool.html
   

9. Open the new page in the browser.

   

10. Stop and then remove your running mysite container.

    $ docker stop mysite
    $ docker rm mysite
    

Upgrade Docker Toolbox

To upgrade Docker Toolbox, download an re-run the Docker Toolbox installer.

Uninstall Docker Toolbox

To uninstall, do the following:

1. List your machines.

   $ docker-machine ls
   NAME                ACTIVE   DRIVER       STATE     URL                         SWARM
   dev                 *        virtualbox   Running   tcp://192.168.99.100:2376
   my-docker-machine            virtualbox   Stopped
   default                      virtualbox   Stopped
   

2. Remove each machine.

   $ docker-machine rm dev
   Successfully removed dev
   

   Removing a machine deletes its VM from VirtualBox and from the~/.docker/machine/machines directory.

3. Remove the Docker Quickstart Terminal and Kitematic from your “Applications” folder.

4. Remove the docker, docker-compose, and docker-machine commands from the /usr/local/bin folder.

   $ rm /usr/local/bin/docker
   

5. Delete the ~/.docker folder from your system.

Learning more

Use docker-machine help to list the full command line reference for Docker Machine. For more information about using SSH or SCP to access a VM, see the Docker Machine documentation.

You can continue with the Docker User Guide. If you are interested in using the Kitematic GUI, see the Kitematic user guide.