Docker Data Volumes and Windows mounts

Docker Desktop
1

Hello –

I have browsed the forums here, lots of google searches, the git-hub documents and anywhere else I have been pointed. The question I cannot seem to get a firm answer for is the following

Does docker volumes for Windows only mount volumes on C:\ ? Or can I create standard windows mounts for a secondary drive letter, like say an E:\

Or do I need to define that at the host level before I create a container so it is available as a separate mount on a E: instead of a C: only mount? Or is windows is stuck with assuming everything resides on c:\ as a root and we are creating mounts to root in a fashion similar to the way you expect for Unix hosts?

2

Is this for running Linux or Windows containers? As long as your share the drives, you can mount them into Linux containers run with Docker for Windows.

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(my machine only has one drive, but had I had more, they would have shown up in that dialog)

3

This is a question geared directly towards windows installations. We are investigating migrating an application into a docker container with Windows 2016 Server Core … but our installations use a separate E: Drive

The only options I have seen so far for Docker are to create Docker Volume containers and mount them to c:\ as a “dir” but that dir is a separate volume from the C: root

I have not found syntax that allows for mounting of a separate volume (MS-SQL server often has 3 extra volumes by Letter in windows for data separation).

Am I just not understanding the syntax, or is the current method only geared towards treating a Windows C: like a *NIX root drive with volumes attached to it?

4

I have the same issue. I was able to create a F: drive that was available in a running container with “VOLUME F:” in the dockerfile. However, I wasn’t able to actually do anything else with the volume in the dockerfile. For example, mkdir F:\somefolder in the dockerfile did not result in F:\somefolder existing in the running container. When I tried to COPY to F: in the dockerfile I got an error during build that docker for Windows only supports copying to the c:\ drive in the image. My workaround was to create the VOLUME F: in the dockerfile, copy to C: in the image, and set the ENTRYPOINT to a PowerShell script that did the F:\ drive operations at container run (e.g mkdir, copy from c: to f:, run processes that expect data on f:).