Volume mount one file or directory straight from Container A to Container B

Question

I want to know if there is a way to volume mount a directory from CONTAINER-A(collector) to CONTAINER-B(store) straight within the same docker network?

I want to do this through the docker-compose file

Currently I have the following:

---
services:
  collector:
    hostname: "collector"
    container_name: "collector"
  volumes_from:
  - container:store
  store:
    hostname: "store"
    container_name: "store"
version: "2.1"

I have a directory in docker container (collector) with some files: /home/collector/data

Which I would like to be volume mounted to a directory somewhere within the docker container: store

Any way to make sure we mount it directory without copying it to somewhere else in the middle first.

I have tried the following but to no avail:

-volumes

-volumes_from

Would appreciate your help, thanks!

Answer 1

Probably best to define a volume at the top level, then mount that into each container, something like this:

---
version: "2.1"

volumes:
  foo: {}

services:

  collector:
    hostname: "collector"
    container_name: "collector"
    volumes:
    - foo:/path/inside/collector

  store:
    hostname: "store"
    container_name: "store"
    volumes:
    - foo:/path/inside/store

This will create you a data volume independent of the two containers. If you recreate the containers, the data will stick around. You can use docker volume <command> to interact with the volume. Alternatively, a simple way to destroy everything is docker-compose down -v.