## Using Docker Machine with a cloud provider Creating a local virtual machine running Docker is useful and fun, but it isn't the only thing Docker Machine can do. Docker Machine supports several “drivers” which let you use the same interface to create hosts on many different cloud or local virtualization platforms. To provision hosts, you use the `docker-machine create` command with the `--driver` flag. Here is example of using the [Digital Ocean](https://digitalocean.com) driver (`digitalocean`) to provision a host on that platform, but there are drivers included for several providers including Amazon Web Services, Google Compute Engine, and Microsoft Azure. Typically, you provide account verification and security credentials for these providers as flags to `docker-machine create`. These flags are unique for each driver. For instance, to pass a Digital Ocean access token you use the `--digitalocean-access-token` flag. Let's take a look at how to do this on Digital Ocean. ## Digital Ocean example To generate your access token: 1. Go to the Digital Ocean administrator console and click on "API" in the header. 2. Click on "Generate New Token". 3. Give the token a clever name (e.g. "machine"), make sure the "Write" checkbox is checked, and click on "Generate Token". 4. Grab the big long hex string that is generated (this is your token) and store it somewhere safe. Now, run `docker-machine create` with the `digitalocean` driver and pass your key to the `--digitalocean-access-token` flag. Example: $ docker-machine create \ --driver digitalocean \ --digitalocean-access-token 0ab77166d407f479c6701652cee3a46830fef88b8199722b87821621736ab2d4 \ staging Creating SSH key... Creating Digital Ocean droplet... To see how to connect Docker to this machine, run: docker-machine env staging For convenience, `docker-machine` will use sensible defaults for choosing settings such as the image that the VPS is based on, but they can also be overridden using their respective flags (e.g. `--digitalocean-image`). This is useful if, for instance, you want to create a nice large instance with a lot of memory and CPUs (by default `docker-machine` creates a small VPS). For a full list of the flags/settings available and their defaults, see the output of `docker-machine create -h`. When the creation of a host is initiated, a unique SSH key for accessing the host (initially for provisioning, then directly later if the user runs the `docker-machine ssh` command) will be created automatically and stored in the client's directory in `~/.docker/machines`. After the creation of the SSH key, Docker will be installed on the remote machine and the daemon will be configured to accept remote connections over TCP using TLS for authentication. Once this is finished, the host is ready for connection. To prepare the Docker client to send commands to the remote server we have created, we can use the subshell method again: $ eval "$(docker-machine env staging)" From this point, the remote host behaves much like the local host we created in the last section. If we look at `docker-machine ls`, we'll see it is now the "active" host, indicated by an asterisk (`*`) in that column: $ docker-machine ls NAME ACTIVE DRIVER STATE URL dev - virtualbox Running tcp://192.168.99.103:2376 staging * digitalocean Running tcp://104.236.50.118:2376 To remove a host and all of its containers and images, use `docker-machine rm`: $ docker-machine rm dev staging Do you really want to remove "dev"? (y/n): y Successfully removed dev Do you really want to remove "staging"? (y/n): y Successfully removed staging $ docker-machine ls NAME ACTIVE DRIVER STATE URL ### Docker supported drivers Docker Machine drivers are available for several other cloud providers. For a full list, see [Supported Drivers](https://docs.docker.com/machine/drivers/). ### Docker Machine command and driver reference * `docker-machine` [create](https://docs.docker.com/machine/reference/create/) command * [Driver options and operating system defaults](https://docs.docker.com/machine/drivers/os-base/) ### 3rd-party driver plugins Several Docker Machine driver plugins for use with other cloud platforms are available from 3rd party contributors. These are use-at-your-own-risk plugins, not maintained by or formally associated with Docker. See [Available driver plugins](https://github.com/docker/machine/blob/master/docs/AVAILABLE_DRIVER_PLUGINS.md) in the docker/machine repo on GitHub. ## Adding a host without a driver You can add a host to Docker which only has a URL and no driver. Therefore it can be used an alias for an existing host so you don’t have to type out the URL every time you run a Docker command. $ docker-machine create --url=tcp://50.134.234.20:2376 custombox $ docker-machine ls NAME ACTIVE DRIVER STATE URL custombox * none Running tcp://50.134.234.20:2376 ## Using Docker Machine with Docker Swarm Docker Machine can also provision [Swarm](https://github.com/docker/swarm) clusters. This can be used with any driver and will be secured with TLS. First, create a Swarm token. Optionally, you can use another discovery service. See the Swarm docs for details. To create the token, first create a Machine. This example will use VirtualBox. $ docker-machine create -d virtualbox local Load the Machine configuration into your shell: $ eval "$(docker-machine env local)" Then run generate the token using the Swarm Docker image: $ docker run swarm create 1257e0f0bbb499b5cd04b4c9bdb2dab3 Once you have the token, you can create the cluster. ### Swarm master Create the Swarm master: docker-machine create \ -d virtualbox \ --swarm \ --swarm-master \ --swarm-discovery token:// \ swarm-master Replace `` with your random token. This will create the Swarm master and add itself as a Swarm node. ### Swarm nodes Now, create more Swarm nodes: docker-machine create \ -d virtualbox \ --swarm \ --swarm-discovery token:// \ swarm-node-00 You now have a Swarm cluster across two nodes. To connect to the Swarm master, use `eval $(docker-machine env --swarm swarm-master)` For example: $ docker-machine env --swarm swarm-master export DOCKER_TLS_VERIFY=1 export DOCKER_CERT_PATH="/home/ehazlett/.docker/machines/.client" export DOCKER_HOST=tcp://192.168.99.100:3376 You can load this into your environment using `eval "$(docker-machine env --swarm swarm-master)"`. Now you can use the Docker CLI to query: $ docker info Containers: 1 Nodes: 1 swarm-master: 192.168.99.100:2376 └ Containers: 2 └ Reserved CPUs: 0 / 4 └ Reserved Memory: 0 B / 999.9 MiB