What is Boot2Docker?
Boot2Docker is a minimalist Linux distribution with the sole purpose to run Docker containers. It was depreciated and is no longer recommended for use.
The Boot2Docker distribution was based on Tiny Core Linux and runs completely from RAM. The ISO installation occupied 27 MB. Boot2Docker started up in around 5 seconds.
The Boot2Docker team encourages users and people in search of a way to run Docker on Microsoft Windows and Apple MacOS to use Docker Machine. The Docker Machine tool installs Docker Engine on virtual hosts. Docker Engine deploys and runs containers from images.
Prior to the release of Docker Machine, Boot2Docker was the only way to run Docker on Windows OSes. The release of Docker Machine, and the subsequent releases of native Docker applications for non-Linux OSes, have deprecated Boot2Docker-CLI. Docker Machine does, however, let users set up a VM that runs Boot2Docker Linux.
Boot2Docker was designed for Docker development only; it lacked many of the capabilities of other Linux OS distributions, such as file sharing between the containers and the native host. Operating in production required a separate Linux host, or a third-party platform such as CoreOS, to manage and orchestrate containers.
Boot2Docker vs. Boot2Docker-CLI
Docker created a Boot2Docker command-line tool, which downloads the Boot2Docker ISO image and automatically creates an Oracle VM VirtualBox virtual machine. Additionally, the tool sets up two networks, one of which connects the containers to the internet and one which creates secure port mapping.
Boot2Docker is included in Docker Toolbox, along with the Kitematic GUI for container management, Docker Engine, Docker Machine, Docker Compose and a shell preconfigured for the Docker command-line interface. Docker Toolbox enables users to run Docker containers on Windows systems that fail to meet the minimum system requirements for the Docker for Windows app.