docs/docs/get-started.md

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Get started with Docker Machine and a local VM

Let's take a look at using docker-machine for creating, using, and managing a Docker host inside of VirtualBox.

First, ensure that the latest VirtualBox is correctly installed on your system.

If you run the docker-machine ls command to show all available machines, you will see that none have been created so far.

$ docker-machine ls
NAME   ACTIVE   DRIVER   STATE   URL

To create one, we run the docker-machine create command, passing the string virtualbox to the --driver flag. The final argument we pass is the name of the machine - in this case, we will name our machine "dev".

This command will download a lightweight Linux distribution (boot2docker) with the Docker daemon installed, and will create and start a VirtualBox VM with Docker running.

$ docker-machine create --driver virtualbox dev
Creating CA: /home/username/.docker/machine/certs/ca.pem
Creating client certificate: /home/username/.docker/machine/certs/cert.pem
Image cache does not exist, creating it at /home/username/.docker/machine/cache...
No default boot2docker iso found locally, downloading the latest release...
Downloading https://github.com/boot2docker/boot2docker/releases/download/v1.6.2/boot2docker.iso to /home/username/.docker/machine/cache/boot2docker.iso...
Creating VirtualBox VM...
Creating SSH key...
Starting VirtualBox VM...
Starting VM...
To see how to connect Docker to this machine, run: docker-machine env dev

You can see the machine you have created by running the docker-machine ls command again:

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

Next, as noted in the output of the docker-machine create command, we have to tell Docker to talk to that machine. You can do this with the docker-machine env command. For example,

$ eval "$(docker-machine env dev)"
$ docker ps

Note: If you are using fish, or a Windows shell such as Powershell/cmd.exe the above method will not work as described. Instead, see the env command's documentation to learn how to set the environment variables for your shell.

This will set environment variables that the Docker client will read which specify the TLS settings. Note that you will need to do that every time you open a new tab or restart your machine.

To see what will be set, run docker-machine env dev.

$ docker-machine env dev
export DOCKER_TLS_VERIFY="1"
export DOCKER_HOST="tcp://172.16.62.130:2376"
export DOCKER_CERT_PATH="/Users/<your username>/.docker/machine/machines/dev"
export DOCKER_MACHINE_NAME="dev"
# Run this command to configure your shell:
# eval "$(docker-machine env dev)"

You can now run Docker commands on this host:

$ docker run busybox echo hello world
Unable to find image 'busybox' locally
Pulling repository busybox
e72ac664f4f0: Download complete
511136ea3c5a: Download complete
df7546f9f060: Download complete
e433a6c5b276: Download complete
hello world

Any exposed ports are available on the Docker hosts IP address, which you can get using the docker-machine ip command:

$ docker-machine ip dev
192.168.99.100

For instance, you can try running a webserver (nginx in a container with the following command:

$ docker run -d -p 8000:80 nginx

When the image is finished pulling, you can hit the server at port 8000 on the IP address given to you by docker-machine ip. For instance:

$ curl $(docker-machine ip dev):8000
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

You can create and manage as many local VMs running Docker as you please- just run docker-machine create again. All created machines will appear in the output of docker-machine ls.

If you are finished using a host for the time being, you can stop it with docker-machine stop and later start it again with docker-machine start. Make sure to specify the machine name as an argument:

$ docker-machine stop dev
$ docker-machine start dev