Let’s assume that we have an nginx container depends on php container you can use volume_from as of now
By this approach the volumes of php are exposed to nginx which is not a desired one but until depends_on feature is introduced.
There is a proposal to introduce "depends_on" in the new networking feature introduced by Docker.
The feature depends_on could be used to order the container start-up.
For more information please go through the following tutorial to get more info about docker: