How to use --volume option with Docker Toolbox on

Question

How can I share a folder between my Windows files and a docker container, by mounting a volume with simple --volume command using Docker Toolbox on?

I'm using "Docker Quickstart Terminal" and when I try this:

winpty docker run -it --rm --volume /C/Users/myuser:/myuser ubuntu

I have this error:

Invalid value "C:\\Users\\myuser\\:\\myuser" for flag --volume: bad mount mode specified : \myuser
See 'docker run --help'.

Following this, I also tried

winpty docker run -it --rm --volume "//C/Users/myuser:/myuser" ubuntu

and got

Invalid value "\\\\C:\\Users\\myuser\\:\\myuser" for flag --volume: \myuser is not an absolute path
See 'docker run --help'.

Answer 1

For those using Virtual Box who prefer command-line approach

1) Make sure the docker-machine is not running

Docker Quickstart Terminal:

docker-machine stop

2) Create the sharing Windows <-> docker-machine

Windows command prompt:
(Modify following to fit your scenario. I feed my Apache httpd container from directory synced via Dropbox.)

set VBOX=D:\Program Files\Oracle\VirtualBox\VBoxManage.exe
set VM_NAME=default
set NAME=c/htdocs
set HOSTPATH=%DROPBOX%\htdocs
"%VBOX%" sharedfolder add "%VM_NAME%" --name "%NAME%" --hostpath "%HOSTPATH%" --automount

3) Start the docker-machine and mount the volume in a new container

Docker Quickstart Terminal:
(Again, I am starting an Apache httpd container, hence that port exposing.)

docker-machine start
docker run -d --name my-apache-container-0 -p 80:80 -v /c/htdocs:/usr/local/apache2/htdocs my-apache-image:1.0

Answer 2

This is an improvement of the selected answer because that answer is limited to c:\Users folder. If you want to create a volume using a directory outside of c:\Users this is an extension.

In windows 7, I used docker toolbox. It used Virtual Box.

1. Open virtual box
2. Select the machine (in my case default).
3. Right clicked and select settings option
4. Go to Shared Folders
5. Include a new machine folder.

For example, in my case I have included:

**Name**: c:\dev
**Path**: c/dev

6. Click and close
7. Open "Docker Quickstart Terminal" and restart the docker machine.

Use this command:

$ docker-machine restart

To verify that it worked, following these steps:

1. SSH to the docker machine.

Using this command:

$ docker-machine ssh

2. Go to the folder that you have shared/mounted.

In my case, I use this command

$ cd /c/dev

3. Check the user owner of the folder. You could use "ls -all" and verify that the owner will be "docker"

You will see something like this:

docker@default:/c/dev$ ls -all
total 92
drwxrwxrwx    1 docker   staff         4096 Feb 23 14:16 ./
drwxr-xr-x    4 root     root            80 Feb 24 09:01 ../
drwxrwxrwx    1 docker   staff         4096 Jan 16 09:28 my_folder/

In that case, you will be able to create a volume for that folder.

You can use these commands:

docker create -v /c/dev/:/app/dev --name dev image
docker run -d -it --volumes-from dev image

or

docker run -d -it -v /c/dev/:/app/dev image

Both commands work for me. I hope this will be useful.

Answer 3

As of August 2016 Docker for windows now uses hyper-v directly instead of virtualbox, so I think it is a little different. First share the drive in settings then use the C: drive letter format, but use forward slashes. For instance I created an H:\t\REDIS directory and was able to see it mounted on /data in the container with this command:

docker run -it --rm -v h:/t/REDIS:/data redis sh

The same format, using drive letter and a colon then forward slashes for the path separator worked both from windows command prompt and from git bash.

I found this question googling to find an answer, but I couldn't find anything that worked. Things would seem to work with no errors being thrown, but I just couldn't see the data on the host (or vice-versa). Finally I checked out the settings closely and tried the format they show:

So first, you have to share the whole drive to the docker vm in settings here, I think that gives the 'docker-machine' vm running in hyper-v access to that drive. Then you have to use the format shown there, which seems to only exist in this one image and in no documentation or questions I could find on the web:

docker run --rm -v c:/Users:/data alpine ls /data