Driver options and operating system defaults

Driver options and operating system defaults

When Docker Machine provisions containers on local network provider or with a remote, cloud provider such as Amazon Web Services, you must define both the driver for your provider and a base operating system. There are over 10 supported drivers and a generic driver for adding machines for other providers.

Each driver has a set of options specific to that provider. These options provide information to machine such as connection credentials, ports, and so forth. For example, to create an Azure machine:

Grab your subscription ID from the portal, then run docker-machine create with these details:

$ docker-machine create -d azure --azure-subscription-id="SUB_ID" --azure-subscription-cert="mycert.pem" A-VERY-UNIQUE-NAME

To see a list of providers and review the options available to a provider, see the reference for that driver.

In addition to the provider, you have the option of identifying a base operating system. It is an option because Docker Machine has defaults for both local and remote providers. For local providers such as VirtualBox, Fusion, Hyper-V, and so forth, the default base operating system is Boot2Docker. For cloud providers, the base operating system is the latest Ubuntu LTS the provider supports.

To use a different base operating system on a remote provider, specify the provider’s image flag and one of its available images. For example, to select a debian-8-x64 image on DigitalOcean you would supply the --digitalocean-image=debian-8-x64 flag.

If you change the base image for a provider, you may also need to change the SSH user. For example, the default Red Hat AMI on EC2 expects the SSH user to be ec2-user, so you would have to specify this with --amazonec2-ssh-user ec2-user.