docker - Can I specify host directory to mount from Dockerfile

Question

Docker run command has option to mount host directory into container

-v=[]: Create a bind mount with: [host-dir]:[container-dir]:[rw|ro]. 
       If "host-dir" is missing, then docker creates a new volume.

And Dockerfile has VOLUME instruction

VOLUME ["/data"] - The VOLUME instruction will add one or more new volumes 
                   to any container created from the image.

From what I see, there is no way to specify host-dir or rw/ro status when using Dockerfile.

Is there any other use of VOLUME in docker file other than wanting to share it with some other container?

Answer 1

Dockerfiles are meant to be portable and shared. The host-dir volume is something 100% host dependent and will break on any other machine, which is a little bit off the Docker idea.

Because of this, it is only possible to use portable instructions within a Dockerfile. If you need a host-dir volume, you need to specify it at run-time.

A common usage of VOLUME from Dockerfile is to store configuration or website sources so that it can be updated later by another container.