Docker In Windows Bash

Unfortunately, you can't run docker in Windows bash today. When you try to run docker in the bash subsystem you get an error like:

Client:
 Version:      17.03.1-ce
 API version:  1.27
 Go version:   go1.7.5
 Git commit:   c6d412e
 Built:        Mon Mar 27 17:10:36 2017
 OS/Arch:      linux/amd64

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

That error may be quite puzzling since the Docker install succeeds from winthin the bash window. However, the docker deamon is not - as the error states - running in the subsystem. ps -e will confirm that there is no dockerd.

If you already have Docker for Windows (https://docs.docker.com/docker-for-windows/) running on your machine it's running outside of the WSL (the Windows Subsystem for Linux). Docker for Windows by listens for commands from the client on TCP and Named Pipes. The named pipe isn't accessible from the WSL, but the client can connect from WSL to the docker Windows Service via TCP.

Sounds backwards, but it's true. How? Easy:

0. If you don't already, Install Docker for Windows
1. Launch a WSL bash window
2. Follow installation steps for Docker on Ubuntu - since Windows subsystem is based on Ubuntu
3. Connect to the docker daemon using tcp instead of the linux socket or a windows pipe. Either add a -H pararmeter when you invoke docker

$ docker -H tcp://localhost version
Client:
 Version:      17.03.1-ce
 API version:  1.27
 Go version:   go1.7.5
 Git commit:   c6d412e
 Built:        Mon Mar 27 17:10:36 2017
 OS/Arch:      linux/amd64

Server:
 Version:      17.03.1-ce
 API version:  1.27 (minimum version 1.12)
 Go version:   go1.7.5
 Git commit:   c6d412e
 Built:        Fri Mar 24 00:00:50 2017
 OS/Arch:      linux/amd64
 Experimental: true

or set the DOCKER_HOST environment variable

$ export DOCKER_HOST=tcp://localhost
$ docker version
Client:
 Version:      17.03.1-ce
 API version:  1.27
 Go version:   go1.7.5
 Git commit:   c6d412e
 Built:        Mon Mar 27 17:10:36 2017
 OS/Arch:      linux/amd64

Server:
 Version:      17.03.1-ce
 API version:  1.27 (minimum version 1.12)
 Go version:   go1.7.5
 Git commit:   c6d412e
 Built:        Fri Mar 24 00:00:50 2017
 OS/Arch:      linux/amd64
 Experimental: true