Docker - cannot mount volume over existing file, file exists

Question

I\'m trying to build a data container for my application in Docker. I run this command to expose some volumes:

docker run --name svenv.nl-data -v /etc/environmen         


        

Answer 1

I guess because you are not mounting a file but instead declaring a mount. Try this notation instead: -v <full path to a file you want to overwrite the target with>:/etc/environment

Answer 2

Suppose you are under Linux, run the following code

docker run -it --rm -v /local_dir:/image_root_dir/mount_dir image_name

Here is some detail:

-it: interactive terminal 
--rm: remove container after exit the container
-v: volume or say mount your local directory to a volume

Since the mount function will 'cover' the directory in your image, your should always make a new directory under your images root directory.

Visit official documentation Use bind mounts to get more information.

Answer 3

You should use:

-v /etc/environment:/etc/environment

instead of:

-v /etc/environment

The former maps container volume to the host volume. The latter tries to create a new volume at /etc/environment and fails since this directory already exists.